Greenheck Fan Fan 470656 User Manual

Part #470656  
IG/IGX Make-Up Air Unit  
®
Installation, Operation and Maintenance Manual  
Please read and save these instructions. Read carefully before attempting to assemble, install, operate or maintain the  
product described. Protect yourself and others by observing all safety information. Failure to comply with instructions  
could result in personal injury and/or property damage! Retain instructions for future reference.  
General Safety Information  
Only qualified personnel should install this unit.  
Personnel should have a clear understanding of these  
instructions and should be aware of general safety  
precautions. Improper installation can result in electric  
shock, possible injury due to coming in contact with  
moving parts, as well as other potential hazards.  
Other considerations may be required if high winds  
or seismic activity are present. If more information  
is needed, contact a licensed professional engineer  
before moving forward.  
DANGER  
Always disconnect power before working on or  
near a unit. Lock and tag the disconnect switch or  
breaker to prevent accidental power up.  
CAUTION  
When servicing the unit, motor may be hot enough  
to cause pain or injury. Allow motor to cool before  
servicing.  
1. Follow all local electrical and safety codes, as well  
as the National Electrical Code (NEC), the National  
Fire Protection Agency (NFPA), where applicable.  
Follow the Canadian Electrical Code (CEC) in  
Canada.  
2. The rotation of the wheel is critical. It must be free  
to rotate without striking or rubbing any stationary  
objects.  
FOR YOUR SAFETY  
If you smell gas:  
1. Open windows.  
2. Do not touch electrical switches.  
3. Extinguish any open flame.  
4. Immediately call your gas supplier.  
3. Motor must be securely and adequately grounded.  
FOR YOUR SAFETY  
4. Do not spin fan wheel faster than the maximum  
cataloged fan rpm. Adjustments to fan speed  
significantly affects motor load. If the fan RPM is  
changed, the motor current should be checked to  
make sure it is not exceeding the motor nameplate  
amps.  
The use and storage of gasoline or other  
flammable vapors and liquids in open  
containers in the vicinity of this appliance is  
hazardous.  
WARNING  
5. Do not allow the power cable to kink or come  
in contact with oil, grease, hot surfaces, or  
Improper installation, adjustment,  
alteration, service or maintenance can  
cause property damage, injury or death.  
Read the installation, operating and  
maintenance instructions thoroughly before  
installing or servicing this equipment.  
chemicals. Replace cord immediately if damaged.  
6. Verify that the power source is compatible with the  
equipment.  
7. Never open blower access doors while the fan is  
running.  
Model IG / IGX Make-Up Air  
1
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3. After storage period, purge grease before putting  
fan into service.  
Sequence of Operation, Furnace –  
2:1 Staged . . . . . . . . . . . . . . . . . . . . . . . . . . . .38  
2:1 Modulation . . . . . . . . . . . . . . . . . . . . . . 39-40  
Operation of Controller –  
4:1 Modulation/8:1 Staged Controller. . . . 40-41  
Sequence of Operation, Furnace –  
4:1 Modulation . . . . . . . . . . . . . . . . . . . . . . 41-42  
8:1 Staged . . . . . . . . . . . . . . . . . . . . . . . . . 43-44  
Ignition Controller . . . . . . . . . . . . . . . . . . . . . . . . . .44  
Economizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45  
Indirect Gas Fired Unit Installations  
Units are listed for installation in the United States and  
Canada.  
• Installation of gas fired duct furnaces must conform  
with local building codes. In the absence of local  
codes, installation must conform to the National  
Fuel Gas code, ANSI Z223.1 or in Canada, CAN/  
CGA-B149 installation codes.  
Troubleshooting  
Blower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46  
Motor Over Amps . . . . . . . . . . . . . . . . . . . . . . . . . .47  
Insufficient / Too Much Airflow. . . . . . . . . . . . . . . .48  
Excessive Noise / Vibration . . . . . . . . . . . . . . . . . .49  
Furnace – Staged . . . . . . . . . . . . . . . . . . . . . . . . . .50  
2:1 Modulation. . . . . . . . . . . . . . . . . . . .51  
4:1 Modulation. . . . . . . . . . . . . . . . . 52-53  
8:1 Staged . . . . . . . . . . . . . . . . . . . . 54-55  
Optional Evaporative Cooling. . . . . . . . . . . . . . . . .56  
Optional Water Wizard™ . . . . . . . . . . . . . . . . . . . .57  
• All electrical wiring must be in accordance with the  
regulation of the National Electrical Code, ANSI/  
NFPA 70.  
• Unit is approved for installation downstream from  
refrigeration units. In these conditions, condensate  
could form in the duct furnace and provision must be  
made to dispose of the condensate.  
Maintenance  
Routine . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58-59  
Fall . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60-61  
Table of Contents  
Installation  
Reference  
Clearance to Combustibles/Service Clearances. . .3  
Indoor Unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4  
Unit Arrangement DB / HZ . . . . . . . . . . . . . . . . . . 4-5  
Roof Mounted Unit – Arrangement DBC . . . . . . . 5-6  
Optional Evaporative Cooling Module. . . . . . . . . . .7  
Venting – Outdoor . . . . . . . . . . . . . . . . . . . . . . . . . . .7  
Indoor, All Units. . . . . . . . . . . . . . . . . . . . .8  
Vent Connections . . . . . . . . . . . . . . . . . . . . . . . . . .62  
Model IG – Single or 2 Stage . . . . . . . . . . . . . . . . .63  
8:1 Staged . . . . . . . . . . . . . . . . . . . . . .64  
2:1 Modulation . . . . . . . . . . . . . . . . . . .65  
4:1 Modulation . . . . . . . . . . . . . . . . . . .66  
Model IGX – Blower Control Center. . . . . . . . . . . .67  
Single or 2 Stage . . . . . . . . . . . . . . . . .68  
Standard Indoor . . . . . . . . . . . . . . . . . . . .9  
Concentric, General . . . . . . . . . . . . . . . .10  
Concentric, Horizontal . . . . . . . . . . . 10-11  
Concentric, Vertical. . . . . . . . . . . . . . 11-12  
Two Pipe, Horizontal. . . . . . . . . . . . . . . .13  
Two Pipe, Vertical . . . . . . . . . . . . . . . . . .14  
8:1 Staged . . . . . . . . . . . . . . . . . . . . . .68  
2:1 Modulation . . . . . . . . . . . . . . . . . . .69  
4:1 Modulation . . . . . . . . . . . . . . . . . . .69  
Performance Table . . . . . . . . . . . . . . . . . . . . . . . . .70  
Start-Up Checklist. . . . . . . . . . . . . . . . . . . . . . . . . .71  
Maintenance Log . . . . . . . . . . . . . . . . . . . Backcover  
Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . Backcover  
Electrical Wiring . . . . . . . . . . . . . . . . . . . . . . . . 15-16  
Gas Piping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17  
Optional Evaporative Cooler Piping. . . . . . . . . 18-19  
Optional Water Wizard™ . . . . . . . . . . . . . . . . . 19-20  
Optional Direct Expansion (DX) Coil Piping. . . 20-21  
Optional Chilled Water Coil Piping. . . . . . . . . . . . .22  
Optional Building Pressure Control . . . . . . . . . . . .22  
Clearance to Combustibles /  
Service Clearances  
Floor  
0 inches 0 inches 0 inches 0 inches  
(0 mm) (0 mm) (0 mm) (0 mm)  
Top  
Sides  
Ends  
Start-Up  
Indirect Fired  
Units*  
Blower . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23-24  
Furnace – All Units . . . . . . . . . . . . . . . . . . . . . . . . .25  
Single Stage. . . . . . . . . . . . . . . . . . . . . .25  
Clearance to combustibles is defined as the minimum  
distance required between the heater and adjacent  
combustible surfaces to ensure the adjacent surface’s  
temperature does not exceed 90 degrees above the ambient  
temperature.  
2:1 Staged . . . . . . . . . . . . . . . . . . . . . . .26  
8:1 Staged . . . . . . . . . . . . . . . . . . . . 26-28  
2:1 Modulation. . . . . . . . . . . . . . . . . . . .29  
4:1 Modulation. . . . . . . . . . . . . . . . . 30-31  
*Reference venting guidelines for combustion blower clearances.  
Optional Economizer . . . . . . . . . . . . . . . . . . . . . . .32  
Optional Evaporative Cooling. . . . . . . . . . . . . . . . .33  
Optional Water Wizard™ . . . . . . . . . . . . . . . . . 34-35  
Recommended Minimum Service Clearances  
Housing 32  
and less  
42 inches (1067 mm) on the  
controls side of the unit  
Operation  
Optional Water Wizard™ . . . . . . . . . . . . . . . . . . . .35  
Optional VAV Units . . . . . . . . . . . . . . . . . . . . . . . . .36  
Optional Recirculating Units. . . . . . . . . . . . . . . . . .37  
Clearances for component removal (such as evaporative  
cooler media) should be 6 in. wider than the width of the  
module itself.  
Model IG / IGX Make-Up Air  
3
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Installation of Indoor Unit  
Installation of Arrangement DB / HZ  
1. Install Curb and/or Equipment  
Support(s)  
NOTE  
To prevent premature heat exchanger failure, do not  
locate units where chlorinated, halogenated, or acid  
vapors are present.  
Position curb/equipment support(s) on the roof  
(reference the CAPS submittal for placement of curb/  
equipment support(s) in relation to the unit). Verify that  
unit supports are level, shim if necessary. Attach curb  
to roof and flash into place. Attach the equipment  
support(s) to the roof, remove metal cover, flash to  
wooden nailer and reinstall cover.  
1. Install Hangers  
Install threaded hangers from ceiling supports. When  
locating hangers, allow enough room to open access  
panel(s). Two nuts must be used on the end of each  
threaded hanger. Ceiling supports are supplied by  
others.  
Roof Curb  
Metal Cover  
2. Install Unit  
Raise the unit into place. Using two nuts per hanger,  
fasten the unit supports to hangers under the unit.  
Appropriate unit supports, such as the optional  
manufacturer hanging bracket kit or c-channel and  
angle iron (supplied by others) should be used.  
Equipment  
Support  
Roof Curb and Equipment Support  
Using self-tapping screws, attach ductwork to unit. In  
order to prevent the unit from swinging and to provide  
a safe environment for service and maintenance,  
additional measures must be taken to secure the unit  
in all directions.  
2. Install Ductwork  
Good duct practices should be followed for all  
ductwork. All ductwork should be installed in  
accordance with SMACNA and AMCA guidelines,  
NFPA 96 and all local codes. Reference the CAPS  
submittal for ductwork sizes.  
Ductwork  
Ceiling Supports  
Supply Air Ductwork  
(Arrangement DB only)  
Hangers  
Ductwork  
NOTE  
Unit Supports  
The use of a duct adapter is recommended on a  
downblast (DB) arrangement to align the ductwork  
with the supply unit. The duct adapter is only a  
guide and is not to be used as support for the  
ductwork.  
Indoor Mounting  
NOTE  
Two nuts must be used on each end of each  
threaded hanging rod for proper support.  
WARNING  
3. Apply Sealant  
Apply an appropriate sealant around the perimeter of  
the curb and duct adapter(s) to isolate fan vibration  
and prevent water penetration.  
All factory-provided lifting lugs must be used when  
lifting any unit. Failure to comply with this safety  
precaution could result in property damage, serious  
injury or death.  
4. Install Unit  
Use a crane and a set of  
spreader bars  
NOTE  
Good duct practices should be followed for  
all ductwork. Ductwork should be installed in  
accordance with SMACNA and AMCA guidelines,  
NFPA 96 and any local codes. Reference the CAPS  
submittal for duct sizes.  
hooked to the  
factory lifting lugs  
to lift and center  
the unit on the  
curb/equipment  
support(s).  
3. Install Vent Piping  
Refer to the Indoor Venting Instructions. Refer to your  
unit submittal to determine the correct venting option.  
Use self-tapping  
sheet metal  
screws to fasten  
the unit to the  
curb/equipment  
NOTE  
Vent piping is supplied by others and not supplied  
by manufacturer.  
support(s).  
Setting Unit  
Model IG / IGX Make-Up Air  
4
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2. Install Combination Curb Adaptor  
Install combination curb adaptor over curb, use wood  
screws to lag in place. Locate extension so the tall  
louvered side is over the exhaust opening, as shown  
in illustration. Caulk extension to combination curb  
adaptor. Fasten extension to curb adaptor with #12  
sheet metal screws (field provided).  
NOTE  
The use of all lifting lugs and a set of spreader bars  
is mandatory when lifting the unit.  
NOTE  
Some units come with the weatherhood attached  
and step 5 may not apply.  
Exhaust  
1 inch  
Inside  
Flange  
5. Assemble and Attach Weatherhood  
The weatherhood can now be assembled and  
attached to the unit. Detailed assembly instructions  
can be found with the weatherhood. If the optional  
evaporative cooling module was selected, this step  
does not apply, refer to the installation instructions  
for the Optional Evaporative Cooling Module section,  
page 7.  
Supply  
6. Seal Weatherhood Seam  
Using an appropriate sealant, seal the seam between  
the weatherhood and the unit.  
Combination Extension  
3. Install Ductwork  
Good duct practices should be followed for all  
ductwork. All ductwork should be installed in  
accordance with SMACNA and AMCA guidelines,  
NFPA 96 and any local codes. Reference the CAPS  
submittal for ductwork size and location.  
Complete Rooftop Installation  
Exhaust  
Ductwork  
by Others  
Supply  
Ductwork  
by Others  
Installation of Roof Mounted Unit  
Arrangement DBC  
1. Install Curb/Equipment Support(s)  
Position curb/equipment support(s) on the roof  
(reference the CAPS submittal for placement of curb/  
equipment support(s) in relation to the unit). Verify  
that all unit supports are level, shim if necessary.  
Attach curb to roof and flash into place. Attach the  
equipment support(s) to the roof, remove metal cover,  
flash to wooden nailer and reinstall cover.  
Ductwork  
NOTE  
The use of a duct adapter is recommended on a  
downblast (DBC) arrangement to align the ductwork  
with the supply unit. The duct adapter is only a guide  
and is not to be used as support for the ductwork.  
Roof Curb  
Metal Cover  
Equipment  
Support  
Roof Curb and Equipment Support  
NOTE  
Refer to Outdoor Venting instructions when locating  
the unit.  
Model IG / IGX Make-Up Air  
5
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7. Install Supply Unit  
Installation of Roof Mounted Unit  
Arrangement DBC, continued  
Use a crane and a set of spreader bars hooked to the  
factory lifting lugs to lift and center the unit on the  
extension/equipment support(s).  
4. Apply Sealant  
Use self-tapping sheet metal screws to fasten the unit  
to the extension/equipment support(s).  
Apply an appropriate sealant around the perimeter of  
the curb and duct adapter(s) to isolate fan vibration  
and prevent water penetration.  
Exhaust Duct Installed  
Sealant  
Supply Duct with  
Duct Adapter Installed  
Sealing Ductwork  
5. Install Exhaust Fan  
Fasten exhaust fan to curb extension with self-tapping  
sheet metal screws.  
Installing Supply Unit  
NOTE  
Exhaust Fan  
The use of all lifting lugs and a set of spreader bars  
is mandatory when lifting unit.  
NOTE  
Be sure to complete the outdoor venting installation  
instructions.  
NOTE  
Some units come with the weatherhood attached  
and step 8 may not apply.  
Installing Exhaust Fan  
NOTE  
8. Assemble and Attach Weatherhood  
The weatherhood can now be assembled and/or  
attached to the unit. Detailed assembly instructions  
can be found with the weatherhood. If the optional  
evaporative cooling module was selected, this step  
does not apply, refer to the Installation Instructions  
for the Optional Evaporative Cooling Module section,  
page 7.  
Installing the exhaust fan prior to the supply unit will  
allow for easier installation of options.  
6. Install Exhaust Options  
Install optional hinge kit with restraining cables and  
grease trap with drain connection.  
9. Seal Weatherhood Seam  
Using an appropriate sealant, seal the seam between  
the weatherhood and the unit.  
NOTE  
NFPA 96 requires that the exhaust fan be hinged.  
Complete Combination Installation  
Model IG / IGX Make-Up Air  
6
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Installation of Evaporative Cooling  
Module (optional)  
Installation of Venting for Outdoor  
Units  
NOTE  
1. Follow Guidelines  
All of the following guidelines must be followed when  
installing the unit.  
Small evaporative coolers ship attached to the base  
unit and require no additional mounting.  
1. Locate Equipment Support(s)  
Position equipment support(s) on the roof (reference  
WARNING  
Do not install units in locations where flue products  
can be drawn into adjacent building openings such  
as windows, fresh air intakes, etc. Distance from  
vent terminal to adjacent public walkways, adjacent  
buildings, operable windows, and building openings  
shall conform with the local codes. In the absence  
of local codes, installation shall conform with the  
National Fuel Gas Code, ANSI Z223.1, or the CAN/  
CGA B-149 Installation Codes.  
the CAPS submittal for  
placement of equipment  
support(s) in relation to  
the unit). Verify that all unit  
supports are level, shim if  
necessary. Attach equipment  
support to the roof, remove  
metal cover, ash to wooden nailer and  
reinstall cover.  
Metal Cover  
Equipment  
Support  
Equipment Support  
Sealant  
WARNING  
2. Apply Sealant  
Apply an appropriate sealant around the  
airstream opening to create an air tight  
seal.  
The following guidelines must be followed for all  
outdoor units:  
1. Building materials that will be affected by flue  
gases should be protected.  
2. Maintain minimum horizontal clearance of 4 feet  
from electric meters, gas meters, regulators,  
and relief equipment. In Canada, the minimum  
clearance is 6 feet.  
Sealant  
3. Set Evaporative Cooling Module  
Use a crane and a set of spreader bars hooked to the  
factory lifting lugs  
to lift and center  
the module on the  
equipment support(s).  
The flange on the  
evaporative cooler  
should overlap the  
3. The combustion blower discharge on outdoor  
units must be located a minimum of 42 inches  
from any combustible materials.  
4. Do not modify or obstruct the combustion  
air inlet cover or the combustion blower  
weatherhood.  
flange on the unit.  
Placing Evaporative Module  
5. Do not add vents other than those supplied by  
the manufacturer.  
6. During the winter, keep the unit clear of snow to  
prevent any blockage of the combustion venting.  
NOTE  
The use of all lifting lugs and a set of spreader bars is  
mandatory when lifting the evaporative cooling module.  
4. Secure Cooling Module to Unit  
Use self-tapping screws to fasten the cooling module  
to the base unit along the  
top and down both sides.  
Fasten at the top through  
2. Install Stack (Optional)  
Clearance may require an exhaust stack. Install an  
exhaust stack as needed to the exhaust connection  
on the unit. Install a vent terminal on the exhaust pipe.  
the flanges. To fasten the  
sides, the media must  
be removed. To remove  
the media, first remove  
the access panel on  
the evaporative module  
Securing Evaporative Module  
and disconnect the evaporative pump(s). The media  
will now slide out. With the media removed, you can  
access the side fastening points inside the evaporative  
module. With all the screws in place, reinstall the media,  
reconnect the pumps and reinstall the access panel.  
NOTE  
When mounting the evaporative cooler, it is  
important that it is level to ensure proper operation  
and water drainage.  
Model IG / IGX Make-Up Air  
7
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Venting Methods  
Installation of Venting for Indoor  
Units  
There are three venting methods for indoor mounted  
units. For each method, the units can be vented  
horizontally through an exterior wall or vertically  
through the roof. Specific venting instructions are  
provided for each method and shown in the following  
pages. Construct the vent system as shown in these  
instructions. Refer to your unit specific submittal to  
determine the applicable venting option.  
WARNING  
The following guidelines must be followed for all indoor  
units:  
1. Installation of venting must conform with local  
building codes. In the absence of local codes,  
installation must conform with the National Fuel  
Gas Code, ANSI Z223.1 or in Canada, CAN/  
CGA-B149 installations codes.  
The venting method options are:  
Standard Indoor Venting  
uses building air for combustion  
vents exhaust to outdoors  
one exterior roof or wall penetration  
2. For the exhaust pipe, use pipe approved for a  
category III appliance or single wall, 26 gauge  
or heavier galvanized vent pipe. The piping is  
required to be gas tight by ANSI.  
Separated Combustion Concentric Venting  
3. For the combustion air pipe on separated  
combustion units, sealed single-wall galvanized  
air pipe is recommended.  
4. The joints must be sealed with a metallic tape or  
Silastic™ suitable for temperatures up to 350°F.  
5. A minimum of 12 inches of straight vent pipe is  
recommended after the exhaust connection and  
before any elbows.  
uses outside air for combustion  
vents exhaust to outdoors  
one exterior roof or wall penetration  
Separated Combustion 2-Pipe Venting  
uses outside air for combustion  
vents exhaust to outdoors  
two exterior roof or wall penetrations  
6. Vertical combustion air pipes should be fitted with  
a tee, drip leg and clean-out cap to prevent any  
moisture in the combustion air pipe from entering  
the unit.  
7. To reduce condensation, insulate any vent runs  
greater than 5 feet.  
NOTE  
For each method, the units can be vented  
horizontally through an exterior wall or vertically  
through the roof. Refer to the specific venting  
instructions for your unit. Construct the vent system  
as shown in these instructions.  
8. All vent pipe connections should be made with at  
least three corrosion resistant sheet metal screws.  
9. Refer to the National Fuel Gas Code for additional  
piping guidelines.  
NOTE  
Vent piping is supplied by others and not supplied  
by manufacturer.  
NOTE  
The drip leg should be cleaned out periodically  
during the heating season.  
NOTE  
Clearances from combustible material for indoor  
units are determined by the National Fuel Gas Code  
and/or other local codes.  
Model IG / IGX Make-Up Air  
8
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Vent Pipe Diameter  
Select the vent pipe diameter. Use only the specified  
pipe diameter.  
Installation of Standard Indoor  
Venting  
Standard Indoor Venting uses one penetration through  
an exterior wall or roof for venting the flue exhaust.  
The combustion air is supplied from the air inside the  
building. Units must not be installed in a potentially  
explosive, flammable, or corrosive atmosphere. To  
prevent premature heat exchanger failure, do not  
locate unit where chlorinated, halogenated or acid  
vapors are present.  
Furnace Size Exhaust Pipe Diameter  
(MBH)  
75 - 175  
200 - 400  
(inches)  
4
6
Installing Exhaust Vent Pipe  
Install the vent pipe with a minimum downward slope  
(from the unit) of 1/4-inch per foot (horizontal venting  
only). Securely suspend the pipe from overhead  
structures at points no greater than 3 feet apart.  
The minimum vent length is 5 feet for horizontal and  
10 feet for vertical. The maximum vent length is 70  
feet. The total equivalent vent length must include  
elbows. The equivalent length of a 4 inch elbow is 6  
feet and the equivalent length of a 6 inch elbow is 10  
feet. Attach the vent terminal to the end of the exhaust  
pipe.  
When units are installed in tightly sealed buildings,  
provisions should be made to supply an adequate  
amount of infiltration air from the outside. The rule of  
thumb is that an opening of one square inch should be  
provided for every 1000 BTUs per hour of input rating.  
Vent terminals must be used. Construct the vent  
system as shown in the drawings. Reference the Vent  
Pipe Diameter table and Exhaust Vent Pipe table for  
additional details.  
Vent  
Length  
Minimum Maximum  
Exterior  
Wall  
(feet)  
(feet)  
A = 12 inch minimum  
5
70  
Horizontal  
Vertical  
10  
70  
Pitch vent pipe  
downward  
from furnace  
¼ inch per foot  
A
EXHAUST  
Air Inlet  
Exhaust  
Vent  
Terminal  
Standard Indoor Venting - Horizontal  
A = 12 inch minimum  
B = 12 inch minimum,  
but should size  
according to expected  
snow depth  
Exhaust Vent  
Terminal  
B
Roof Line  
A
Air Inlet  
Standard Indoor Venting - Vertical  
Model IG / IGX Make-Up Air  
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Installation of Concentric Venting  
(General)  
Concentric venting allows the exhaust pipe and  
combustion air pipe to pass through a single hole in  
the roof or wall of the building. A concentric venting  
adapter (CVA) is required for concentric venting.  
Concentric Venting – Horizontal  
Refer to the diagram below for venting on horizontal  
concentric systems. Maintain at least 12 inches from  
the combustion air inlet guard to the exhaust vent  
terminal (Dim. B). To prevent water from running  
into the combustion air pipe and to allow for easy  
installation of the combustion air inlet guard, the  
combustion air pipe must terminate at least 2 inches  
from the exterior surface of the outside wall (Dim. A).  
The concentric venting adapter is designed for indoor  
installations and should never be installed on the  
exterior of the building.  
The exhaust pipe must terminate with the vent  
terminal. For horizontal venting, the combustion air  
pipe must terminate with the combustion air guard.  
For vertical venting, the combustion air pipe must  
terminate with the inlet terminal. Depending on what  
was ordered, one of these vent terminals will be  
provided in the optional venting kit along with the  
concentric venting adapter (CVA).  
A = 2 inch minimum  
Exterior  
B = 12 inch minimum  
Wall  
Mounting  
Bracket  
A
B
EXHAUST  
Exhaust  
Vent  
COMBUSTION AIR  
Terminal  
If venting vertically through the roof, refer to the  
vertical concentric venting instructions. If venting  
horizontally through the wall, refer to the horizontal  
concentric venting instructions.  
Mounting  
Bracket  
Combustion  
Air Inlet Guard  
Pitch vent pipe downward  
from furnace 1/4 inch per foot  
NOTE  
Vent Connection Diameter  
Vent piping is supplied by others and not supplied  
by manufacturer.  
Vent terminals must be used (one vent terminal  
included with each furnace). Construct the vent  
system as shown in the drawings and refer to the  
table for the correct vent connection diameters.  
Non-Concentric Vent  
Concentric Vent  
Connection Diameter Connection Diameter  
Furnace  
Size (MBH)  
Exhaust Combustion Air Exhaust Combustion Air  
(inches)  
(inches)  
(inches)  
(inches)  
4
6
4
6
4
6
6
8
75-175  
200-400  
Vent Length  
CVA-4  
CVA-6  
Refer to table for minimum and maximum vent  
lengths. The total equivalent vent length must include  
elbows. The equivalent length of a 4 inch elbow is  
6 feet and the  
equivalent length  
of a 6 inch elbow  
is 10 feet.  
4-inch Concentric  
Venting Adapter  
6-inch Concentric  
Venting Adapter  
Vent  
Length  
Minimum Maximum  
(feet)  
(feet)  
Combustion Air Connection  
Concentric Side  
5
70  
Exhaust Connection  
Concentric Side  
Horizontal  
1. Determine Venting Location  
Determine the location of the concentric venting  
adapter (CVA) based on any clearances that must  
be maintained (follow all codes referenced in these  
instructions).  
CVA  
2. Attach Mounting Brackets  
Attach field-supplied, corrosion resistant mounting  
brackets to the CVA using corrosion resistant sheet  
metal screws.  
Combustion Air Connection  
Non-Concentric Side  
Exhaust Connection  
Non-Concentric Side  
Top View  
Model IG / IGX Make-Up Air  
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3. Install Exhaust Pipe  
Concentric Venting – Vertical  
Slide the exhaust pipe through the CVA. Provide  
enough exhaust piping to pass through the wall (or  
floor) and provide the minimum clearance of 12 inches  
between the exhaust pipe termination and the  
combustion air intake. With all required clearances  
satisfied, attach the exhaust pipe to the CVA.  
Refer to the diagram below for venting on vertical  
concentric systems. Maintain at least 12 inches  
between the top of the combustion air inlet terminals  
and the bottom of the exhaust terminal. (Dim. B).  
The bottom of the combustion air intake pipe must  
terminate above the snow line or at least 12 inches  
above the roof, whichever is greater.  
INTAKE END  
A tee with cleanout must be provided on the  
combustion air and exhaust pipe to prevent debris  
from entering the heat exchanger.  
Exhaust Connection  
(Model IGX)  
Exhaust Connection  
(Model IG)  
A = 12 inch minimum, but  
should size according to  
expected snow depth  
Exhaust Vent  
Terminal  
B = 12 inch minimum  
C = 12 inch minimum  
DISCHARGE  
B
END  
Combustion Air  
Inlet Terminal  
A
Roof Line  
Mounting  
Bracket  
Mounting  
Bracket  
Combustion Air Connection  
(Model IGX)  
Combustion Air Connection  
(Model IG)  
4. Install Combustion Air Pipe  
Attach a field-supplied combustion air pipe to the  
concentric side of the CVA.  
C
Be sure to provide enough combustion air piping  
to pass through the wall and provide the minimum  
clearance of 2 inches between the combustion air  
intake and the exterior surface of the outside wall.  
Tee with  
drip leg and  
clean-out cap  
C
Be sure to maintain the minimum clearance of  
12 inches between the exhaust pipe termination and  
the combustion air intake.  
Vent Connection Diameter  
5. Install CVA Assembly  
Vent terminals must be used. Construct the vent  
system as shown in the drawings and refer to the  
table for the correct vent connection diameters.  
Place the CVA assembly through the wall and verify  
that all minimum clearance requirements as specified  
in these instructions are met. Secure the CVA  
assembly to the wall with corrosion resistant sheet  
metal screws through the mounting brackets.  
Non-Concentric Vent  
Connection Diameter Connection Diameter  
Concentric Vent  
Furnace  
Size (MBH)  
Exhaust Combustion Air Exhaust Combustion Air  
6. Attach CVA Assembly to Unit  
(inches)  
(inches)  
(inches)  
(inches)  
Attach the exhaust pipe to the unit’s combustion  
exhaust. Using an additional combustion air pipe,  
connect the unit’s combustion air supply intake to the  
combustion air connection on the CVA.  
4
6
4
6
4
6
6
8
75-175  
200-400  
Vent Length  
7. Install Combustion Air Inlet Guard and  
Exhaust Vent Terminal  
Slide the combustion air inlet guard over the exhaust  
pipe and fasten it to the combustion air pipe. Attach  
the exhaust vent terminal to the discharge end of the  
exhaust piping on the outside of the building.  
Refer to table for minimum and maximum vent  
lengths. The total equivalent vent length must include  
elbows. The equivalent length of a 4 inch elbow is  
6 feet and the  
Vent  
Minimum Maximum  
equivalent length  
of a 6 inch elbow  
is 10 feet.  
Length  
(feet)  
(feet)  
10  
70  
Vertical  
8. Seal Opening  
Seal the opening between the wall and the air intake  
pipe using an appropriate method.  
1. Determine Venting Location  
Determine the location of the concentric venting  
adapter (CVA) based on any clearances that must  
be maintained (follow all codes referenced in these  
instructions).  
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2. Attach Mounting Brackets  
7. Install Combustion Air Inlet Guard and  
Exhaust Vent Terminal  
Slide the combustion air terminal over the vent pipe  
and fasten it to the combustion air pipe. Attach the  
exhaust vent terminal to the discharge end of the  
exhaust piping.  
Attach field-supplied, corrosion resistant, mounting  
brackets to the CVA using corrosion resistant sheet  
metal screws.  
3. Install Exhaust Pipe  
Slide the exhaust pipe through the CVA. Provide  
enough exhaust piping to pass through the roof and  
provide the minimum clearance of 12 inches between  
the exhaust pipe termination and the combustion air  
intake. With all required clearances satisfied, attach  
the exhaust pipe to the CVA.  
8. Seal Opening  
Seal the opening between the roof line and the air  
intake pipe using an appropriate method.  
INTAKE END  
Exhaust Connection  
(Model IGX)  
Exhaust Connection  
(Model IG)  
DISCHARGE  
END  
Combustion Air Connection  
(Model IGX)  
Combustion Air Connection  
(Model IG)  
4. Install Combustion Air Pipe  
Attach a field-supplied combustion air pipe to the  
concentric side of the CVA.  
Be sure to provide enough combustion air piping  
to pass through the roof and provide the minimum  
clearance of 12 inches between the combustion  
air intake and the exterior surface of the roof. This  
clearance may need to be increased to allow for snow  
accumulation.  
Be sure to maintain the minimum clearance of  
12 inches between the exhaust pipe termination and  
the combustion air intake.  
5. Install CVA Assembly  
Place the CVA assembly through the roof and verify  
that all minimum clearance requirements as specified  
in these instructions are met. Secure the CVA  
assembly to the ceiling with corrosion resistant sheet  
metal screws through the mounting brackets.  
6. Attach CVA Assembly to Unit  
Attach the exhaust pipe to the unit’s combustion  
exhaust. Using an additional combustion air pipe,  
connect the unit’s combustion air supply intake to the  
combustion air connection on the CVA.  
Be sure to include the required tee’s with drip legs and  
clean-outs.  
Model IG / IGX Make-Up Air  
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2. Install Combustion Air Pipe  
Installation of Two Pipe Venting –  
Horizontal  
Refer to the diagram below for venting on horizontal  
concentric systems. Maintain at least 12 inches of  
clearance between the exhaust pipe termination and  
the exterior surface of the exterior wall (Dim. A).  
Run a combustion air pipe from the unit’s combustion  
air intake through the exterior wall to the outdoors.  
The combustion air pipe must terminate at least 12  
inches from the combustion vent pipe and 24 inches  
from the exterior surface of the outside wall. Attach  
the combustion air inlet guard to the end of the  
combustion air pipe. Using field-supplied mounting  
brackets, support the combustion air pipe as needed.  
The combustion air pipe must be a minimum of 12  
inches from the exhaust pipe and 24 inches from the  
exterior surface of the outside wall (Dim. B).  
3. Seal Wall Openings  
Using an appropriate method, seal the wall openings  
around the piping.  
A minimum of 1 inch and a maximum of 48 inches  
of building wall thickness is required for separated  
combustion vent pipe.  
INTAKE END  
A = 12 inch minimum  
Exterior  
Wall  
B = 24 inch minimum  
C = 12 inch minimum  
Exhaust  
Vent  
Terminal  
Exhaust Connection  
(Model IGX)  
Exhaust Connection  
(Model IG)  
B
A
EXHAUST  
C
Pitch vent pipe  
downward  
COMBUSTION AIR  
DISCHARGE  
from furnace  
¼ inch per foot  
END  
Two (2) field-supplied  
support brackets  
Combustion  
Air Inlet  
Terminal  
Combustion Air Connection  
(Model IGX)  
Combustion Air Connection  
(Model IG)  
Vent Connection Diameter  
Vent terminals must be used. The optional vent kit  
includes two terminals. Construct the vent system as  
shown in the drawings and refer to the table for the  
correct vent connection diameters.  
Furnace Size  
(MBH)  
Exhaust  
(inches)  
Combustion  
(inches)  
4
6
4
6
75 - 175  
200 - 400  
Vent Length  
Refer to table for minimum and maximum vent  
lengths. The minimum vent length is 5 feet and the  
maximum vent length is 50 feet. The total equivalent  
vent length must include elbows. The equivalent  
length of a 4 inch elbow is 6 feet and the equivalent  
length of a 6 inch elbow is 10 feet.  
Vent  
Minimum Maximum  
Length  
(feet)  
(feet)  
5
50  
Horizontal  
1. Install Exhaust Pipe  
Run an exhaust pipe from the unit’s combustion  
exhaust through the exterior wall to the outdoors. The  
exhaust pipe must terminate at least 12 inches from  
the outside surface of the outside wall. Attach exhaust  
vent terminal to the end of the exhaust pipe. Using  
field-supplied mounting brackets, support the exhaust  
pipe as needed.  
Model IG / IGX Make-Up Air  
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1. Install Exhaust Pipe  
Installation of Two Pipe Venting –  
Vertical  
Run an exhaust pipe from the unit’s combustion  
exhaust through the roof to the outdoors. The exhaust  
pipe must terminate at least 12 inches above the  
outside surface of the roof. This clearance may need  
to be increased to accommodate snow accumulation.  
Attach the exhaust vent terminal to the end of the  
exhaust pipe.  
Refer to the diagram below for venting on vertical  
concentric systems. The combustion air pipe must  
terminate at least 12 inches above the roof. This  
clearance may need to be increased to accommodate  
for snow accumulation. The exhaust must terminate at  
least 12 inches above and 12 inches horizontally from  
the combustion air inlet.  
2. Install Combustion Air Pipe  
Run a combustion air pipe from the unit’s combustion  
air intake through the roof to the outdoors. The  
combustion air pipe must terminate at least 12 inches  
horizontally and vertically from the combustion  
exhaust pipe and at least 24 inches from the exterior  
surface of the roof. These clearances may need to  
be increased to accommodate for expected snow  
accumulation. Attach the combustion air terminal to  
the end of the combustion air pipe.  
C
Exhaust Vent  
Combustion  
Terminal  
Air Inlet  
Terminal  
B
A
Roof Line  
3. Seal Roof Penetration  
Using an appropriate method, seal the roof openings  
around the vent pipes.  
D
Tee with  
drip leg and  
clean-out cap  
INTAKE END  
D
A = 12 inch minimum, but should size  
according to expected snow depth  
Exhaust Connection  
(Model IGX)  
Exhaust Connection  
(Model IG)  
B = 24 inch minimum  
C = 12 inch minimum  
D = 12 inch minimum  
DISCHARGE  
Vent Connection Diameter  
END  
Vent terminals must be used. Construct the vent  
system as shown in the drawings and refer to the  
table for the correct vent connection diameters.  
Furnace Size  
(MBH)  
Exhaust  
(inches)  
Combustion  
(inches)  
Combustion Air Connection  
(Model IGX)  
Combustion Air Connection  
(Model IG)  
4
6
4
6
75 - 175  
200 - 400  
Vent Length  
Refer to table for minimum and maximum vent  
lengths. The minimum vent length is 10 feet and the  
maximum vent length is 70 feet. The total equivalent  
vent length must include elbows. The equivalent  
length of a 4 inch elbow is 6 feet and the equivalent  
length of a 6 inch elbow is 10 feet.  
Vent  
Minimum Maximum  
Length  
(feet)  
(feet)  
10  
70  
Vertical  
Model IG / IGX Make-Up Air  
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1. Determine the Size of the Main Power  
Lines  
Installation - Electrical Wiring  
The unit’s nameplate states the voltage and the unit’s  
total MCA. The main power lines to the unit should be  
sized accordingly. The nameplate is located on the  
outside of the unit on the control panel side.  
IMPORTANT  
Before connecting power to the unit, read and  
understand the following instructions and wiring  
diagrams. Complete wiring diagrams are attached  
on the inside of the control center door(s).  
Voltage, Hertz, Phase  
IMPORTANT  
All wiring should be done in accordance with the  
latest edition of the National Electrical Code ANSI/  
NFPA 70 and any local codes that may apply. In  
Canada, wiring should be done in accordance with  
the Canadian Electrical Code.  
VOLTS  
HZ  
EXH HP  
MOP  
PH  
SUP HP  
MCA  
CAUTION  
Unit’s Total MCA  
If replacement wire is required, it must have a  
temperature rating of at least 105ºC, except for  
energy cut-off or sensor lead wire which must be  
rated to 150ºC.  
Electrical Nameplate  
2. Provide the Opening(s) for the  
IMPORTANT  
Electrical Connections  
Electrical openings vary by unit size and arrangement  
and are field-supplied.  
The equipment must be properly grounded. Any  
wiring running through the unit in the airstream must  
be protected by metal conduit, metal clad cable or  
raceways.  
3. Connect the Main Power  
Connect the main power lines to the disconnect  
switch and main grounding lug(s). Torque field  
connections to 20 in.-lbs.  
DANGER  
High voltage electrical input is needed for this  
equipment. This work should be performed by a  
qualified electrician.  
4. Wire the Optional Convenience Outlet  
The convenience outlet requires a separate 115V  
power supply circuit. The circuit must include short  
circuit protection which may need to be supplied by  
others.  
CAUTION  
Any wiring deviations may result in personal injury or  
property damage. Manufacturer is not responsible  
for any damage to, or failure of the unit caused by  
incorrect final wiring.  
5. Wire the Optional Accessories  
Reference the ladder diagram on the inside of the  
control center door for correct wiring of the following  
accessories:  
IMPORTANT  
Manufacturer’s standard control voltage is 24 VAC.  
Control wire resistance should not exceed 0.75 ohms  
(approximately 285 feet total length for 14 gauge  
wire; 455 feet total length for 12 gauge wire). If the  
resistance exceeds 0.75 ohms, an industrial-style,  
plug-in relay should be wired in place of the remote  
switch. The relay must be rated for at least 5 amps  
and have a 24 VAC coil. Failure to comply with these  
guidelines may cause motor starters to chatter or  
not pull in, resulting in contactor failures and/or  
motor failures.  
• Selectra Stat  
• Room Override  
• Blower Switch  
• Heat Switch  
• Dirty Filter Indicator  
• TSCP  
• KSCP  
• Economizer Activator  
• Room Stat  
• Indicating Lights  
NOTE  
Wiring to the Selectra Stat or room override should  
be in separate conduit or run with shielded cable.  
NOTE  
The TSCP and KSCP remote panels have number-  
to-number wiring.  
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6. Wire the Evaporative Cooler (optional)  
Reference the ladder diagram on the inside of the  
control center door for correct wiring of the pump and  
the optional water valves.  
NOTE  
Large evaporative coolers may require a separate  
power supply.  
7. Install Economizer Sensors (optional)  
All economizer options (EC) require an outdoor air  
temperature or enthalpy sensor to be field installed  
inside of the weatherhood and field wired to terminals  
SO+ and SO- on the economizer.  
Economizer options EC-3 and EC-4 require an outdoor  
air temperature or enthalpy sensor to be field installed  
in the return air duct and field wired to terminals SR+  
and SR- on the economizer.  
The sensors are provided by the factory and ship with  
the unit.  
8. Install Discharge Air Sensor (optional)  
For units with 8:1, 16:1 or 24:1 staged turndown,  
install the discharge air sensor at least three duct  
diameters downstream of the heat exchanger. The  
discharge air sensor can be found in the unit’s control  
center.  
9. Install DDC Interface (Optional)  
Some units may use an external signal from a building  
management system to control the dampers and/or  
discharge air temperature. Reference the unit ladder  
diagram for the correct wiring.  
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1. Determine the Supply Gas  
Installation of Gas Piping  
Requirements  
The unit’s nameplate states the requirements for the  
gas being supplied to the unit.  
IMPORTANT  
All gas piping must be installed in accordance  
with the latest edition of the National Fuel Gas  
Code ANSI/Z223.1 and any local codes that may  
apply. In Canada, the equipment shall be installed  
in accordance with the Installation Code for Gas  
Burning Appliances and Equipment (CGA B149)  
and Provincial Regulations for the class. Authorities  
having jurisdiction should be consulted before  
installations are made.  
Minimum gas pressure for maximum output  
MAX BTU/HR  
BTU/H MAX  
MIN BTU/HR  
BTU/H MIN  
NORMAL MANIFOLD  
PRESSURE  
PRESSION DÕADMISSION  
NORMALE  
MIN GAS PRESSURE  
FOR MAX OUTPUT  
PRESSION DE GAZ MIN  
POUR PUISSANCE MAX  
“W.C.  
“W.C.  
“W.C.  
MAX GAS  
MIN GAS  
PRESSURE  
PRESSION DE GAZ  
PRESSURE  
PRESSION DE GAZ  
MAX  
“W.C.  
PSI  
IMPORTANT  
DESIGN DT  
DT NORMALE  
TYPE OF GAS  
NATURE DU GAZ  
F
All piping should be clean and free of any foreign  
material. Foreign material entering the gas train can  
cause damage.  
EQUIPPED FOR  
CONCU POUR  
AGAINST  
EXTERNAL STATIC PRESSURE  
SCFM  
“W.C.  
CONTE  
PRESSION STATIQUE EXTERIEURE  
WARNING  
Type of gas  
Maximum gas pressure  
All components of this or any other gas fired heating  
unit must be leak tested prior to placing the unit  
into operation. A soap and water solution should be  
used to perform this test. NEVER test for gas leaks  
with an open flame.  
Indirect Gas Nameplate  
2. Install Additional Regulator if Required  
When the supply gas pressure exceeds the maximum  
gas pressure shown on the unit’s nameplate, an  
additional regulator (by others) is required to reduce  
IMPORTANT  
the pressure. The  
regulator must have a  
listed leak limiting device  
or it must be  
vented to the  
outdoors.  
Do NOT connect the unit to gas types other than  
what is specified and do NOT connect the unit to  
gas pressures that are outside of the pressure range  
shown on the label.  
Supply Gas Pressure Range  
(in. wg)  
Minimum  
Maximum  
Natural  
LP  
6
14  
14  
10  
WARNING  
When leak testing pressures equal to or less than  
14 in. wg (3.5 kPa), first close the field-installed  
shutoff valve to isolate the unit from the gas supply  
line.  
3. Connect the Supply Gas Line  
A manual shut off valve (gas cock), 1/8 inch plugged  
test port and 6 inch drip leg must be installed prior  
to the gas train. The valve and the test port must  
be accessible for the connection of a test gauge.  
NOTE  
To  
When connecting the gas supply, the length of the  
run must be considered in determining the pipe size  
to avoid excessive pressure drop. Refer to a Gas  
Engineer’s Handbook for gas pipe capacities.  
Supply gas  
connections  
must be  
made by  
a qualified  
installer  
Controls  
Gas Cock  
Ground Joint Union  
From  
Gas  
Supply  
NOTE  
1/8 in. Plugged Tap  
6 in. Trap  
and are not  
furnished by  
Each furnace has a single 3/4-inch connection.  
manufacturer.  
Supply Gas Line  
4. Test the System for Leaks  
Check both the supply lines and the factory piping for  
leaks. Apply a soap and water solution to all piping  
and watch for bubbling which indicates a leak.  
WARNING  
NEVER test for a gas leak with an open flame.  
WARNING  
The factory piping has been checked for leaks, but  
should be rechecked due to shipping and installation.  
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Installation - Evaporative Cooler  
Piping (optional)  
Evaporative Cooling with Recirculating Pump  
Evaporative Cooling with Auto Drain and Fill  
Supply Line  
Supply Line  
Sump Overflow  
VALVE A  
Supply Solenoid  
(normally closed)  
Supply Line Valve  
(normally closed)  
Sump Drain  
Drain Line Valve  
(normally open)  
VALVE C  
Sump Drain Solenoid  
(normally open)  
Drain Line  
Overflow  
VALVE B  
Trap  
Trap  
Supply Line Drain Solenoid  
(normally open)  
Drain Line  
Recirculating Evaporative Piping  
IMPORTANT  
Auto Drain & Fill Evaporative Piping  
IMPORTANT  
The supply line should be of adequate size and  
pressure to resupply the amount of water lost due to  
bleed-off and evaporation. The drain line should be  
the same size or larger than the supply line.  
All supply solenoids, valves and all traps must be below  
the roofline or be otherwise protected from freezing.  
IMPORTANT  
The supply line should be of adequate size and  
pressure to resupply the amount of water lost due to  
bleed-off and evaporation. The drain line should be  
the same size or larger than the supply line.  
CAUTION  
All solenoid valves and traps must be installed  
below the roof to protect the supply water line from  
freezing. If they cannot be installed below the roof,  
an alternative method must be used to protect the  
lines from freezing.  
CAUTION  
Provisions must be taken to prevent damage to the  
evaporative cooling section during freezing conditions.  
The sump, drain lines and supply lines must be  
drained prior to freezing conditions or an alternate  
method must be used to protect the lines and media.  
IMPORTANT  
The supply solenoid (Valve A) is NOT the same as  
the drain solenoids (Valve B and Valve C). Make sure  
to use the proper solenoid for each location. Check  
your local code requirements for proper installation  
of this type of system.  
1. Install the Water Supply Line  
Supply line opening requirements vary by unit size  
and arrangement and are field-supplied. Connect the  
water supply line to the float valve through the supply  
line opening in the evaporative cooling unit. Install a  
manual shutoff valve in the supply line.  
Auto Drain & Flush Valves  
(when provided by manufacturer)  
Mfg.  
Part  
ASCO™  
Part  
Assembly  
Number  
Solenoid De-Energized  
2. Install the Drain Line  
Diameter Qty.  
Type  
Position  
Connect an unobstructed drain line to the drain and  
overflow connections on the evaporative cooler. A  
manual shut off valve (by others) is required for the  
evaporative cooler  
Number Number  
1/2 inch  
1
461262 8210G2  
Supply  
Closed  
(12.7 mm)  
Supply  
Line  
Drain  
drain line. A trap  
1/4 inch  
1
852178 461263 8262G262  
461264 8210G35  
Open  
Open  
should be used to  
6 in. min.  
(6.35 mm)  
prevent sewer gas  
from being drawn  
into the unit.  
Drain  
Trap  
6 in. min.  
Sump  
Drain  
3/4 inch  
1
(19.05 mm)  
Part numbers subject to change.  
3. Check/Adjust Water Level  
Check the water level in the sump tank. The water  
level should be above the pump intake and below the  
overflow. Adjust the float as needed to achieve the  
proper water level.  
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TM  
1. Install the Water Supply Line  
Supply line opening requirements vary by unit size  
and arrangement and are field-supplied. Connect the  
water supply line to the float valve through the supply  
line opening in the evaporative cooling unit. Install  
the 1/2 inch normally closed solenoid (Valve A) in the  
supply line. Install the 1/4 inch normally open solenoid  
(Valve B) between the supply line and the drain line as  
shown.  
Installation of Water Wizard (optional)  
Evaporative Cooling with the Water Wizard™  
NOTE  
The following instructions are provided for  
evaporative coolers equipped with the Water  
Wizard™ only. Additional instructions are provided  
for evaporative coolers equipped with the auto drain  
and fill or bleed-off.  
2. Install the Drain Line  
WARNING  
Connect an unobstructed drain line to the sump drain  
overflow connection. Install the 3/4 in. normally open  
solenoid (Valve C) between the sump drain connection  
and the drain line. A  
Disconnect and lock-out all power and gas before  
performing any maintenance or service to the unit.  
Failure to do so could result in serious injury or  
death and damage to equipment.  
trap should be used to  
prevent sewer gas from  
being drawn into the  
unit. Refer to Drain Trap  
drawing.  
6 in. min.  
Drain  
Trap  
Water Wizard™ Valves  
6 in. min.  
(when provided by manufacturer)  
Mfg.  
Part  
ASCO™  
Part  
Unit  
Model  
Assembly  
Number  
Solenoid De-Energized  
3. Check/Adjust Water Level  
Check the water level in the sump tank. The water  
Diameter Qty.  
Type  
Position  
Number Number  
level should be above the pump intake and below the  
overflow. Adjust the float as needed to achieve the  
proper water level.  
1/2 inch  
1
461262 8210G2 Supply  
Supply  
Closed  
IGX -  
(12.7 mm)  
H12/H22  
852370  
852371  
IGX - H32  
(<9000 cfm)  
1/2 inch  
1
383086 8210G34  
Line  
Open  
Closed  
Open  
(12.7 mm)  
Drain  
3/4 inch  
1
383088 8210G9 Supply  
(19.05 mm)  
IGX - H32  
(≥9000 cfm)  
Supply  
1/2 inch  
1
383086 8210G34  
Line  
(12.7 mm)  
Drain  
Part numbers subject to change.  
1. Install Normally Closed Supply Line/  
Solenoid  
Connect the water supply line to the manual supply  
valve in the unit. Install the supply solenoid in the  
supply line, upstream of the manual supply valve and  
below the roofline.  
2. Install Normally Open Drain Line/  
Solenoid  
Connect the drain line to the supply line between the  
manual supply valve and the supply solenoid. Install a  
drain solenoid in the drain line, below the roof line. A  
trap should be installed in the drain line.  
NOTE  
Solenoid(s) may be provided by manufacturer (if  
ordered) or by others.  
CAUTION  
Any wiring deviations may result in personal injury or  
property damage. Manufacturer is not responsible  
for any damage to or failure of the unit caused by  
incorrect final wiring.  
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Installation of Water Wizard™,  
continued  
Installation - Direct Expansion (DX)  
Coil Piping (optional)  
To Media  
IMPORTANT  
Pressure Gauge  
Factory  
Installed  
Guidelines for the installation of direct expansion  
cooling coils have been provided to ensure proper  
performance and longevity of the coils. These are  
general guidelines that may have to be tailored  
to meet the specific requirements of any one job.  
As always, a qualified party or individual should  
perform the installation and maintenance of any coil.  
Protective equipment such as safety glasses, steel  
toe boots and gloves are recommended during the  
installation and maintenance of the coil.  
Sump Drain  
Manual Supply Valve  
Roof Line  
Supply Solenoid  
(normally closed)  
Field  
Installed  
Supply Line Drain Solenoid  
IMPORTANT  
Trap  
(normally open)  
All field-brazing and welding should be performed  
using high quality materials and an inert gas purge  
(such as nitrogen) to reduce oxidation of the internal  
surface of the coil.  
Water Wizard™ Installation  
3. Wire the Solenoid(s)  
Wire the supply line solenoid and drain solenoid as  
shown on the unit’s wiring diagram in the control  
center.  
IMPORTANT  
All field-piping must be self-supporting and flexible  
enough to allow for the thermal expansion of the coil.  
4. Wire the Temperature Sensor  
If the evaporative cooler shipped separate from the  
unit, the temperature sensor must be wired. The  
sensor wire is bundled inside the discharge end of the  
evaporative cooler. Wire the sensor wire to terminals  
AI2 and AIC on the terminal strip in the unit’s control  
center.  
1. Locate the Distributor(s) by Removing  
the Distributor Access Panel  
NOTE  
The Water Wizard™ start-up must be completed for  
proper performance.  
Distributor Access Panel  
Thermal  
(by others)  
(by others)  
Installation with Hot Gas Bypass  
2. Verify Nozzle Placement  
Inspect the refrigerant  
distributor and verify  
that the nozzle is in  
place. The nozzle is  
generally held in place  
by a retaining ring or is  
an integral part of  
Retainer  
Ring  
Nozzle  
Distributor  
Nozzle Placement  
the distributor itself.  
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for one minute, the system is ready to be charged or  
refrigerant in another portion of the system can be  
opened to the coil. A steady rise in microns would  
indicate that moisture is still present and that the coil  
should be further vacuumed until the moisture has  
been removed.  
NOTE  
If a hot gas bypass kit was provided by others, refer  
to the manufacturer’s instructions.  
3. Install Suction Line  
Install suction line(s) from the compressor to the  
suction connection(s) which are stubbed through the  
side of the cabinet.  
NOTE  
Failure to obtain a high vacuum indicates a great  
deal of moisture or a small leak. Break the vacuum  
with a charge of dry nitrogen or other suitable  
gas and recheck for leaks. If no leaks are found,  
continue vacuuming the coil until the desired  
vacuum is reached.  
4. Install the Liquid Line and Thermal  
Expansion Valve (TEV) (By Others)  
Liquid line openings vary by coil size and  
circuiting and are field-supplied. Follow the TEV  
recommendations for installation to avoid damaging  
the valve. If the valve is externally equalized, use  
a tubing cutter to cut off the plugged end of the  
factory-installed equalizer line. Use a de-burring tool  
to remove any loose metal from the equalizer line and  
attach it to the TEV. If the valve is internally equalized,  
the factory-installed equalizer line can be left as is.  
8. Install the Drain Line  
Connect an  
unobstructed drain  
line to the drain pan. A  
6 in. min.  
trap should be used to  
prevent sewer gas from  
being drawn into the  
unit.  
Drain  
Trap  
6 in. min.  
Coil  
Suction Header  
Distributor  
Equalizer Line  
Liquid Line  
Nozzle  
IMPORTANT  
All traps must be installed below the roof line or be  
otherwise protected from freezing.  
Thermal  
Expansion  
Valve (by others)  
Suction Line  
Remote Sensing Bulb  
Straps  
Suction Connection  
General Installation  
5. Mount the Remote Sensing Bulb  
(By Others)  
The expansion valve’s remote sensing bulb should be  
securely strapped to the horizontal run of the suction  
line at the 3 or 9 o’clock position and insulated.  
6. Check Coil Piping for Leaks  
Pressurize the coil to 100 psig with dry nitrogen or  
other suitable gas. The coil should be left pressurized  
for a minimum of 10 minutes. If the coil holds the  
pressure, the hook-up can be considered leak free.  
If the pressure drops by 5 psig or less, re-pressurize  
the coil and wait another 10 minutes. If the pressure  
drops again, there is likely one or more small leaks  
which should be located and repaired. Pressure losses  
greater than 5 psig indicate a large leak that should be  
isolated and repaired.  
7. Evacuate and Charge the Coil  
Use a vacuum pump to evacuate the coil and any  
interconnecting piping that has been open to the  
atmosphere. Measure the vacuum in the piping using  
a micron gauge located as far from the pump as  
possible. Evacuate the coil to 500 microns or less  
and then close the valve between the pump and the  
system. If the vacuum holds to 500 microns or less  
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Installation of Chilled Water Coil  
Piping (optional)  
Installation of Building Pressure  
Control (optional)  
1. Mount Pressure Tap  
Using the factory provided bracket, mount the  
pressure tap to the  
outside of the unit.  
Choose a location  
out of the prevailing  
winds and away from  
supply or exhaust  
fans to assure  
accurate readings.  
IMPORTANT  
Guidelines for the installation of the cooling coil  
have been provided to ensure proper performance  
of the coils and their longevity. These are general  
guidelines that may have to be tailored to meet the  
specific requirements of any one job. As always,  
a qualified party or individual should perform the  
installation and maintenance of the coil. Protective  
equipment such as safety glasses, steel toe boots  
and gloves are recommended during the installation  
and maintenance of the coil.  
2. Run Pressure Tap Lines  
Run a pressure tap line from the pressure tap on the  
outside of the unit to the low pressure tap on the back  
of the photohelic gauge. Run a second pressure tap  
line from the high pressure tap on the back of the  
photohelic gauge to the space. Fifty feet of tubing is  
supplied with the unit.  
When installing couplings, do not apply undue  
stress to the connection. Use a backup pipe  
wrench to avoid breaking the weld between the coil  
connection and the header.  
All field-piping must be self-supporting. System  
piping should be flexible enough to allow for the  
thermal expansion and contraction of the coil.  
1. Verify Coil Hand Designation  
High  
Pressure  
Tap to  
Factory  
Wiring  
Check the coil hand  
Hot Return  
designation to ensure that  
Connection  
space  
it matches the system.  
Coils are generally  
plumbed with the supply  
connection located on  
the bottom of the leaving  
air-side of the coil and the  
Entering  
Air  
Leaving  
Air  
Low  
Pressure  
Tap to  
outside  
Cold Supply  
Connection  
Connections for Photohelic Gauge  
return connection at the top of the entering air-side  
of the coil. This arrangement provides a counter flow  
heat exchanger and positive coil drainage.  
3. Set the Building Pressure  
The pressure gauge is used to set the desired building  
pressure. The pressure is set by adjusting the knobs  
for the upper and lower pressure limits. Typical  
settings are 0.0 in. wg for the lower and 0.10 in. wg for  
the upper pressure setting.  
2. Check the Coil for Leaks  
Pressurize the coil to 100 psig with dry nitrogen or  
other suitable gas. The coil should be left pressurized  
for a minimum of 10 minutes. If the coil holds the  
pressure, the hook-up can be considered leak free.  
If the pressure drops by 5 psig or less, re-pressurize  
the coil and wait another 10 minutes. If the pressure  
drops again, there is likely one or more small leaks  
which should be located and repaired. Pressure losses  
greater than 5 psig indicate a large leak that should be  
isolated and repaired.  
Pressure Indicating  
Needle  
Pressure Setting  
Needles  
3. Connect the Supply & Return Lines  
Connect the supply and return lines as shown above.  
Pressure Setting Knobs  
4. Install the Drain Line  
Connect an unobstructed  
drain line to the drain pan.  
Typical Photohelic Gauge Settings  
6 in. min.  
A trap should be installed  
Drain  
Trap  
to prevent sewer gas from  
being drawn into the unit.  
6 in. min.  
IMPORTANT  
All traps must be installed below the roof line or be  
otherwise protected from freezing.  
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Start-Up - Blower  
NOTE  
Refer to the Start-Up Checklist in the Reference  
Section Before Proceeding Further!  
Pre Start-Up Check  
Rotate the fan wheel by hand and make sure no  
parts are rubbing. Check the V-belt drive for proper  
alignment and tension (a guide for proper belt tension  
and alignment is provided in the Belt Maintenance  
section). Check fasteners, set screws, and locking  
collars on the fan, bearings, drive, motor base, and  
accessories for tightness.  
To reverse the rotation on three phase units,  
disconnect and lock-out the power, then  
interchange any two power leads.  
NOTE  
To reverse the rotation on single phase units,  
disconnect and lock-out the power, then rewire the  
motor per the manufacturer’s instructions.  
IMPORTANT  
If the blower is rotating in the wrong direction, the  
unit will move some air, but will not perform as  
designed. Be sure to perform a visual inspection to  
guarantee the correct blower rotation.  
WARNING  
Disconnect and lock-out all power and gas before  
performing any maintenance or service to the unit.  
Failure to do so could result in serious injury or  
death and damage to equipment.  
3. Check for Vibration  
Check for unusual noise, vibration or overheating of  
the bearings. Reference the Troubleshooting section  
for corrective actions.  
SPECIAL TOOLS REQUIRED  
• Voltage Meter (with wire probes)  
• Amperage Meter  
IMPORTANT  
• Micro Amp Meter  
• Pressure Gauges – (refrigerant)  
Tachometer  
Excessive vibration may be experienced during  
the initial start-up. Left unchecked, it can cause a  
multitude of problems including structural and/or  
component failure.  
• Thermometer  
• Incline manometer or equivalent  
IMPORTANT  
Generally, fan vibration and noise is transmitted  
to other parts of the building by the ductwork. To  
minimize this undesirable effect, the use of heavy  
canvas duct connectors is recommended.  
WARNING  
Check the housing, blower, and ductwork for any  
foreign objects before running the blower.  
1. Check the Voltage  
4. Motor Check  
Before starting the unit, compare the supplied voltage,  
hertz, and phase with the unit and motor’s nameplate  
Measure the motor’s voltage, amps and RPM.  
Compare to the specifications. Motor amps can be  
reduced by lowering the motor RPM or increasing  
system static pressure.  
information.  
Voltage, Hertz, Phase  
VOLTS  
HZ  
PH  
IMPORTANT  
SUP HP  
MCA  
Additional starters and overloads may be provided  
in the make-up air control center for optional  
exhaust blowers. Any additional overloads must be  
checked for proper voltage, amps and RPMs.  
MOP  
Unit’s Total MCA  
Electrical Nameplate  
2. Check the Blower Rotation  
Open the blower access  
door and run the blower  
momentarily to determine the  
rotation.  
5. Air Volume Measurement & Check  
Measure the unit’s air volume (CFM) and compare it  
with its rated air volume. If the measured air volume  
is off, adjust the fan’s RPM by changing/adjusting the  
drive.  
Arrows are placed on the  
blower scroll to indicate the  
proper direction or reference  
Blower  
Housing  
Blower Rotation  
the example shown.  
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NOTE  
The most accurate way to measure the air volume is  
by using a pitot traverse method downstream of the  
blower. Other methods can be used but should be  
proven and accurate.  
IMPORTANT  
Changing the air volume can significantly increase  
the motor’s amps. If the air volume is changed,  
the motor’s amps must be checked to prevent  
overloading the motor.  
NOTE  
To ensure accuracy, the dampers are to be open  
when measuring the air volume.  
6. Set-up Optional Components  
Adjust the settings on the optional components. See  
the Control Center Layout in the Reference section for  
location of optional components.  
• Heating Inlet Air Sensor  
Typical setting: 60-70ºF  
• Cooling Inlet Air Sensor  
Typical setting: 75ºF  
• Building Freeze Protection  
Typical setting: 5 minutes; 45ºF  
• Dirty Filter Gauge  
Typical setting: Settings vary greatly for each  
unit. See Reference section for adjusting  
information.  
NOTE  
If your unit is equipped with a 4:1 modulation or  
8:1 staged control, the inlet air sensor and building  
freeze protection may be included in the furnace  
controller. If this is the case, instructions for setting  
the inlet air sensor and building freeze protection are  
included in the Furnace Start-Up.  
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Start-Up - Furnaces (all units)  
Available Control Options  
Single Furnace Units  
IMPORTANT  
1:1 Staged  
2:1 Staged  
8:1 Staged  
one 1-stage furnace  
one 2-stage furnace  
one 8-stage furnace  
For the unit to function properly, all stage or  
modulation valves must be set for high and low fire.  
2:1 Electronic  
Modulation  
NOTE  
one 2:1 modulating furnace  
one 4:1 modulating furnace  
There are five furnace control options available. Be  
sure to refer to the specific instructions for your  
control type.  
4:1 Electronic  
Modulation  
Two Furnace Units  
IMPORTANT  
1:1 Staged  
2:1 Staged  
4:1 Staged  
two independent 1-stage furnaces  
two independent 1-stage furnaces  
two independent 2-stage furnaces  
Multi furnace units may use a combination of the  
available control options. Each furnace must be set-  
up per the specific instructions for its control type.  
one 8-stage and  
one 1-stage furnace  
16:1 Staged  
IMPORTANT  
8:1 Electronic  
Modulation  
one 4:1 modulating and  
one 2-stage furnace  
Multi furnace units will use one stage or electronic  
modulation controller per unit and one or two  
ignition controller(s) per furnace. Each furnace will  
have its own gas valve(s). Each valve must be set for  
high and low fire.  
Three Furnace Units  
1:1 Staged  
3:1 Staged  
6:1 Staged  
three independent 1-stage furnaces  
three independent 1-stage furnaces  
three independent 2-stage furnaces  
NOTE  
one 8-stage and  
two 1-stage furnaces  
24:1 Staged  
To force the unit to light for set-up purposes, the  
heat switch must be closed or jumpered out. See  
the Ladder Diagram on the inside of the control  
center door for proper terminals to jumper out.  
one 4:1 modulating,  
one 2-stage and  
one 1-stage furnace  
12:1 Electronic  
Modulation  
NOTE  
Start-Up - Single Stage Control  
If the unit is equipped with an independent  
1. Send Unit to High Fire  
Send the unit to high fire by  
inlet air sensor (not incorporated into the stage  
or modulation controller), the unit will not light  
unless the outside air temperature is less than  
the inlet air sensor setting. If the outside air is  
greater than the inlet air sensor setting, turn the  
setting to its maximum position. When set-up is  
complete, reset the inlet air sensor to the proper  
temperature. If the unit is equipped with a stage or  
electronic modulation controller that includes an  
inlet air sensor function, the inlet air sensor will be  
overridden when the unit is forced to high fire.  
setting the temperature selector to  
its maximum setting.  
Temperature  
Selector  
2. Check the High Fire Manifold  
Pressure  
Using a manometer, measure the burner manifold  
pressure at the manifold pressure test port. Refer to  
the Gas Train Layout in the Reference section for the  
test port location.  
The pressure on high fire  
Single Stage Manifold  
should be 3-1/2 in. wg for  
Pressure (in. wg)  
natural gas and  
10 in. wg for  
LP gas.  
LP  
10  
Natural Gas  
3-1/2  
High Fire  
If needed, use the  
high fire adjustment  
High Fire  
Adjustment  
screw on the staged gas  
valve to adjust the high  
fire manifold pressure.  
Counterclockwise rotation  
will decrease the gas  
pressure and clockwise  
rotation will increase the  
gas pressure.  
3. Reset the Temperature Setting  
Reset the temperature setting on the temperature  
selector to the desired setting.  
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Start-Up - 2:1 Staged Control  
Start-Up - 8:1 Staged Control  
1. Send Unit to High Fire  
Send the unit to high fire by setting  
the temperature selector to its  
IMPORTANT  
8:1 staged furnaces use two manifolds and two  
staged gas valves per furnace. The high and low fire  
manifold pressure must be checked and properly  
set on each manifold.  
Temperature  
maximum setting.  
Selector  
2. Check the High Fire  
Manifold Pressure  
IMPORTANT  
Using a manometer, measure the burner manifold  
pressure at the manifold pressure test port. Refer to  
the Gas Train Layout in the Reference section for the  
test port location.  
Confirm that the discharge air sensor is installed in  
the duct, at least three duct diameters downstream  
of the furnace.  
The pressure on high fire should be 3-1/2 in. wg for  
natural gas and 10 in. wg for LP gas.  
1. Send the Unit to High Fire  
For the furnace to light, the heat switch must be  
closed or jumpered out. Reference the unit ladder  
diagram for proper terminals to jumper.  
If needed, use the high fire adjustment screw on the  
combination gas valve to adjust the high fire manifold  
pressure. Counterclockwise rotation will decrease the  
gas pressure and clockwise rotation will increase the  
gas pressure.  
To send the unit to high fire, press and hold the Up,  
Down and Enter keys. The middle LED light, L2, will  
flash on the screen when the unit is forced to high fire.  
High Fire  
Adjustment  
High Fire  
Terminal  
Low Fire  
Adjustment  
The unit will remain at high fire until the Function key  
is pressed (middle LED light, L2, will stop flashing).  
L1  
L2  
L3  
Function  
Enter  
Up  
Down  
WARNING  
Once the unit is forced to high fire, it will remain at  
high fire until the Function key is pressed.  
3. Send Unit to Low Fire  
Remove and isolate the wire from the high fire terminal  
on the combination gas valve to send the unit to low  
fire.  
NOTE  
Forcing the unit to high fire during warm or hot  
weather conditions may cause the high limit switch  
to trip. If the switch trips, it will reset once the  
discharge air temperature has reached a safe level.  
4. Check the Low Fire Manifold Pressure  
Using a manometer, measure the burner manifold  
pressure at the manifold pressure test port. Refer to  
the Gas Train Layout in the Reference section for the  
2. Check the High Fire Manifold  
Pressure  
Using a manometer, measure the high fire burner  
manifold pressure for each furnace at the pressure  
test port. Refer to the Gas Train Layout in the  
Reference section for the test port location.  
test port location.  
Two Stage Manifold  
Pressure (in. wg)  
The pressure on low fire  
should be 7/8 in. wg  
for natural gas and  
2-1/2 in. wg for LP  
gas.  
LP  
2-1/2  
10  
Natural Gas  
7/8  
Low Fire  
High Fire  
3-1/2  
The recommended high fire manifold pressure is  
3-1/2 in. wg for natural gas and 10 in. wg for LP gas.  
If needed use the low fire adjustment screw on the  
combination gas valve to adjust the low fire manifold  
pressure. Counterclockwise rotation will decrease the  
gas pressure and clockwise rotation will increase the  
gas pressure. Once the low fire manifold pressure is  
set, reattach the high fire wire to the high fire terminal.  
If needed, adjust the high fire screws on each staged  
gas valve to set both high fire manifold pressures.  
Counterclockwise rotation will decrease the gas  
pressure and clockwise rotation will increase the gas  
pressure.  
5. Reset the Temperature Setting  
Reset the temperature setting on the temperature  
selector to the desired setting.  
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6. Access the Discharge Air  
High Fire  
Adjustment  
High Fire  
Terminal  
Low Fire  
Adjustment  
Temperature Setting  
Using the Up or Down key, scroll through the  
Setpoints Menu until the  
display reads “dtS”, then  
press the Enter key. The  
display will change to the  
discharge air temperature  
setting.  
7. Edit the Setting  
Use the Up or Down key to change the discharge  
air temperature setting. When the correct setting is  
displayed, press the Enter key to save the setting and  
return to the Setpoints Menu.  
3. Send the Unit to Low Fire  
Disconnect and isolate the wire from the high fire  
terminal to send the unit to low fire.  
NOTE  
Steps 8 - 9 are provided for adjusting the inlet air  
set point. The inlet air sensor is preset to the factory  
recommended 65ºF, only adjust if needed.  
4. Check the Low Fire Manifold Pressure  
Measure each valve’s low fire manifold pressure.  
The recommended low fire manifold pressure is 7/8 in.  
wg for natural gas and 2-1/2 in. wg for LP.  
NOTE  
The inlet air sensor monitors the temperature of  
the inlet air. If the inlet air is above the sensor’s set  
point, the inlet air sensor shuts off the furnace and  
continues to supply the warm outside air.  
If needed, use the low fire adjustment screw on each  
staged gas valve to properly set both low manifold  
settings. Counterclockwise rotation will decrease the  
gas pressure and clockwise rotation will increase the  
gas pressure.  
8. Access the Inlet Air Sensor Setting  
From the Setpoints Menu, use the Up or Down key to  
navigate through the menu options until the display  
reads “iAS”. Once the  
display reads “iAS”, press  
the Enter key. The display  
When the low fire manifold pressure is properly set,  
reattach the disconnected  
wire to the high fire  
Pressure (in. wg)  
Eight Stage Manifold  
terminal, allow the heat  
Natural Gas  
7/8  
LP  
2-1/2  
10  
switch to close  
or remove the  
jumper.  
Low Fire  
High Fire  
will change to the inlet air  
sensor setting.  
3-1/2  
9. Edit the Setting  
WARNING  
Use the Up or Down key to change the inlet air setting.  
When the correct setting is displayed, press the Enter  
key to save the setting and return to the Setpoints  
Menu.  
Once the high and low fire have been set, be sure  
the press the Function key to end high fire mode.  
The middle LED light, L2, will stop flashing when  
high fire mode is off.  
NOTE  
NOTE  
After modifying a setting, the Enter key must be  
pressed to save the change. If the Enter key is not  
pressed, the display will return to the Setpoints  
Menu without saving the change.  
Step 5-7 are for adjusting the discharge air setting.  
The discharge air temperature setting is factory set  
to the recommended 70ºF. Only adjust the setting if  
needed.  
NOTE  
NOTE  
Steps 10 - 11 are provided for adjusting the room  
override setting. Only adjust the setting if the room  
override function is desired.  
After modifying a setting, the Enter key must be  
pressed to save the change. If the Enter key is not  
pressed the display will return to the setpoints menu  
without saving the change.  
NOTE  
The room override function temporarily changes  
the discharge air temperature to the room override  
setting if the room thermostat is not satisfied.  
5. Access the Setpoints Menu  
Press and hold the Function  
key for three seconds to  
access the Setpoints Menu.  
The display will read “SEt.”  
Model IG / IGX Make-Up Air  
27  
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10. Access the Room Override Setting  
From the Setpoints Menu, use the Up or Down key to  
navigate through the menu  
options until the display  
reads “rot.” Once the display  
reads “rot,” press the Enter  
key. The display will change  
to the room override setting.  
NOTE  
The room override function requires a field-supplied  
thermostat to be installed in the space and to be  
wired between terminal 31 and 32 in the unit’s  
control center. Reference the unit ladder diagram.  
11. Edit the Setting  
Use the Up or Down key to change the room override  
setting. When the correct setting is displayed, press  
the Enter key to save the setting and return to the  
Setpoints Menu.  
Model IG / IGX Make-Up Air  
28  
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Start-Up - 2:1 Electronic Modulation  
NOTE  
The low fire manifold pressure should always be  
rechecked after adjusting the high fire.  
1. Send Unit to High Fire  
Turn the temperature  
Temperature  
Selector  
selector to its maximum  
NOTE  
setting to send the unit  
to high fire.  
Once the high and low fire manifold pressures are  
properly set, reset the discharge air temperature to  
the desired setting.  
2. Check the High Fire Manifold  
Pressure  
With the unit at high fire, use a manometer to measure  
the burner manifold pressure at the manifold pressure  
test port. See the Gas Train Layout in the Reference  
section for the manifold pressure test port location.  
The recommended high fire manifold pressure is  
3-1/2 in. wg for natural gas and 10 in. wg for  
LP gas.  
If needed, use the high  
fire adjustment screw on  
High Fire  
Adjustment  
the shut-off gas valve to  
adjust the high fire manifold  
pressure. Counterclockwise  
rotation will decrease the  
gas pressure and clockwise  
rotation will increase the gas  
pressure.  
3. Send Unit to Low Fire  
Remove and isolate one wire from the modulating gas  
valve terminal to send the unit to low fire.  
4. Check the Low Fire Manifold Pressure  
With the unit at low fire, use a manometer to measure  
the burner manifold pressure at the manifold pressure  
test port. See the Gas Train Layout in the Reference  
section for the manifold pressure test port location.  
The recommended low  
fire manifold pressure is  
7/8 in. wg for  
2:1 Manifold Pressure  
(in. wg)  
Natural Gas  
7/8  
LP  
2-1/2  
10  
natural gas and  
Low Fire  
High Fire  
2-1/2 in. wg  
for LP gas.  
3-1/2  
If needed, use the low fire adjustment screw on the  
modulating gas valve to adjust the low fire manifold  
pressure. Counterclockwise  
Terminal  
rotation will decrease the  
gas pressure and clockwise  
rotation will increase the gas  
pressure.  
Once the low fire is set,  
reattach the disconnected  
wire to the modulating valve  
Low Fire  
and reset the temperature  
Adjustment  
selector.  
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To enter the high fire  
setting mode, press  
and hold button #1  
until the LED lights  
solid red. Release.  
The valve is now in  
the high fire setting  
mode.  
Start-Up - 4:1 Electronic Modulation  
#1  
#2  
1. Send the Unit to High Fire  
To send the unit to high fire, press and hold the Up,  
Down and Enter keys. The unit will remain at high fire  
until the Function key is pressed.  
LED  
Light  
Press or hold button  
#2 to decrease gas  
Function  
Enter  
Up  
flow. Each button press equates to the minimum  
available step size and will decrease flow slowly.  
Holding the button down auto-steps and eliminates  
the need to continuously press the button. Use this  
feature to rapidly decrease the flow.  
Down  
WARNING  
Press or hold button #1 to increase gas flow. Each  
button press equates to the minimum available  
step size and will increase flow slowly. Holding the  
button down auto-steps and eliminates the need to  
continuously press the button. Use this feature to  
rapidly decrease the flow.  
If the unit is forced to high fire, it will remain at high  
fire until the Function key is pressed.  
NOTE  
After modifying a setting, the Enter key must be  
pressed to save the change. If the Enter key is not  
pressed the display will return to the Program Menu  
without saving the change.  
High fire setting should be 3.5 in. wg for natural gas  
and 10.0 in. wg for LP gas.  
To save high fire setting, simultaneously hold button  
#1 and #2 until the LED turns off.  
NOTE  
Forcing the unit to high fire in mild weather  
conditions may cause the high limit switch to trip. If  
the switch trips, it will reset once the discharge air  
temperature is at a safe level.  
NOTE  
Controls left in the high fire setting mode will default  
to the current setting after 5 minutes of inactivity.  
3. Exit High Fire Mode  
2. Check the High Fire Manifold  
Press the Function key to exit high fire mode.  
Pressure  
Before setting high fire on the EXA valve, turn the  
regulator screw on the combination valve all the way  
in (increase pressure).  
4. Send Unit to Low Fire  
Remove the cover on the modulating gas valve. Press  
and hold button #2 until the LED light blinks red;  
release. The unit is now in low fire.  
Using a manometer, measure the high fire manifold  
pressure at the pressure test port. Refer to the Gas  
Train Layout in the Reference section for the test port  
location.  
5. Check the Low Fire Manifold  
Pressures  
With the unit at low fire, use a manometer to check the  
manifold pressure. Refer to the Gas Train Layout in the  
Reference section for the test port location.  
The recommended high fire manifold pressure is  
3-1/2 in. wg for natural gas and 10 in. wg for LP gas.  
If needed, adjust the high  
fire screw on the shut-  
off valve to set the high  
fire manifold pressure.  
Counterclockwise rotation  
will decrease the gas  
pressure and clockwise  
rotation will increase the  
gas pressure.  
The recommended low  
fire manifold pressure  
is 1/3 in. wg for natural  
gas and 1.0 in.  
4:1 Modulation Manifold  
Pressure (in. wg)  
High Fire  
Adjustment  
Natural Gas  
1/3  
LP  
1
Low Fire  
High Fire  
wg for LP gas.  
3-1/2  
10  
To adjust the  
low fire gas pressure, use button #1 and #2 on the  
gas valve. Button #1 will increase the gas pressure,  
while button #2 will decrease the gas pressure. Each  
time the button is pressed, it corresponds to the  
minimum available step size and will slowly change  
the gas pressure. Holding the button down will rapidly  
change the gas pressure. To save the low fire setting,  
stimutaneously hold buttons 1 and 2 until the LED  
turns off.  
Model IG / IGX Make-Up Air  
30  
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10. Edit the Setting  
Note: If the valve remains in the low fire setting mode  
for more than five (5) minutes, it will revert back to its  
previous setting.  
Use the Up or Down key to edit the inlet air setting.  
When the correct setting is displayed, press the Enter  
key to save the setting and return to the Setpoints  
menu.  
NOTE  
The following steps are for adjusting the discharge  
air setting. The discharge air temperature setting is  
factory set to the recommended 70ºF. Only adjust  
the setting if needed.  
NOTE  
Steps 11 and 12 are provided for adjusting the room  
override setting. Only adjust the setting if the room  
override function is desired.  
6. Access the Setpoints Menu  
Press and hold the Function  
key for three seconds to  
access the Setpoints Menu.  
The display will read “SEt”  
when Setpoints Mode is  
active.  
NOTE  
The room override function temporarily changes  
the discharge air temperature to the room override  
setting if a room thermostat is not satisfied.  
11. Access the Room Override Setting  
From the Setpoints Menu, use the Up or Down key to  
navigate through the menu  
7. Access the Discharge Air  
Temperature Setting  
options until the display  
Use the Up or Down keys to  
scroll through the Setpoints  
Menu options until the  
reads “rot.” Once the display  
reads “rot,” press the Enter  
key. The display will change  
to the room override setting.  
display reads “dtS” then  
press the Enter key. The display will change to the  
discharge air temperature setting.  
NOTE  
The room override function requires a field-supplied  
thermostat to be installed in the space and to be  
wired between terminal 31 and 32 in the unit’s  
control center.  
8. Edit the Setting  
Use the Up or Down keys to change the discharge  
air temperature setting. When the correct setting is  
displayed, press the Enter key to save the setting and  
return to the Setpoints Menu.  
12. Edit the Setting  
Use the Up or Down key to change the room override  
setting. When the correct setting is displayed, press  
the Enter key to save the setting and return to the  
Setpoints menu.  
NOTE  
After modifying a setting, the Enter key must be  
pressed to save the change. If the Enter key is not  
pressed the display will return to the Setpoints  
Menu without saving the change.  
NOTE  
After modifying a setting, the Enter key must be  
pressed to save the change. If the Enter key is not  
pressed the display will return to the Setpoints  
Menu without saving the change.  
NOTE  
Steps 9 thru 10 are provided for adjusting the inlet  
air set point. The inlet air sensor is preset to the  
factory recommended 60ºF, only adjust if needed.  
NOTE  
The inlet air sensor monitors the temperature of  
the inlet air. If the inlet air is above the sensor’s set  
point, the inlet air sensor shuts off the furnace and  
continues to supply the warm outside air.  
9. Access the Inlet Air Sensor Setting  
From the Setpoints Menu, use the Up or Down key to  
navigate through the menu options until the display  
reads “iAS.” Once the display  
reads “iAS”, press the Enter  
key. The display will change  
to the inlet air sensor setting.  
Model IG / IGX Make-Up Air  
31  
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Start-Up - Economizer (optional)  
IMPORTANT  
The outside air volume must be measured and  
compared to the total air volume when setting  
the minimum outside air. The minimum outside air  
should never be set based on the inlet damper or  
potentiometer position.  
NOTE  
To prevent premature heat exchanger failure, do not  
locate units where chlorinated, halogenated, or acid  
vapors are present.  
NOTE  
3. Set the Enthalpy Changeover Set  
Point (optional)  
Units with an economizer are designed for either  
0-30% outside air (HV-1), 31-75% outside air  
(HV-2) or 100% return air (HV-3). Refer to the CAPS  
submittal for the unit’s ventilation type.  
If using an economizer, the enthalpy changeover  
setting must be set. If differential temperature or  
differential enthalpy control is used, set the enthalpy  
changeover set point to D. If outside air temperature  
or enthalpy reference is used, set the enthalpy  
changeover set point to the desired setting from the  
following table.  
NOTE  
HV-1 and HV-2 use economizer controls (EC) or  
(MB).  
NOTE  
Enthalpy Changeover Setting  
Economizer control may use outside air temperature  
reference (EC-1), outside enthalpy reference  
(EC-2), differential temperature reference (EC-3) or  
differential temperature reference (EC-4).  
Changeover  
Setting  
Temperature* (°F)  
A
B
C
D
73  
70  
67  
63  
NOTE  
Economizer control may use a potentiometer  
(MB-1), 2-10 VDC signal (MB-2), 4-20mA signal  
(MB-3) or a manual quadrant (MB-4).  
*Temperature at 50% relative humidity, see the  
Honeywell W7212 Economizer instructions for set  
points at other humidities  
1. Verify Sensor Installation  
All economizer options (EC) require an outdoor air  
temperature or enthalpy sensor to be field-installed  
inside of the weatherhood and field-wired to terminals  
SO+ and SO- on the economizer.  
NOTE  
For options EC-3 and EC-4 the enthalpy changeover set  
point is the temperature at which the economizer will  
send the dampers to the minimum outside air position.  
Economizer options EC-3 and EC-4 require an outdoor  
air temperature or enthalpy sensor to be field-installed  
in the return air duct and field-wired to terminals SR+  
and SR- on the economizer.  
4. Program Optional Room Stat  
Program the optional room stat. Separate detailed  
instructions for programming the room stat ship with  
the optional room stat.  
Verify that all economizer sensors needed for your  
application are properly installed and wired.  
2. Set Minimum Outside Air  
Set the minimum outside air position. HV-1 is  
designed for 0-30% outside air and HV-2 is designed  
for 31-75% outside air.  
All economizer options, EC-1, EC-2, EC-3 and  
EC-4 and option MB-1 use a potentiometer to  
set the minimum outside air damper position.  
The potentiometer is located on the economizer  
for options EC-1, EC-2, EC-3 and EC-4. The  
potentiometer may be factory-mounted in the unit  
control center or field-mounted in the space for option  
MB-1.  
MB-2 and MB-3 use an external signal from a building  
management system to position the dampers.  
MB-4 uses a manual quadrant located on the inlet  
damper to position the dampers.  
Model IG / IGX Make-Up Air  
32  
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Bleed-Off  
Valve  
Pump  
Filter  
Supply  
Connection  
Float  
Valve  
Threaded Float  
Adjustment  
Start-Up - Evaporative Cooling  
(optional)  
Overflow  
1. Check the Installation  
The media may  
have been removed  
during installation,  
so its orientation  
45º  
should be double  
checked. The media  
Entering Air  
Leaving Air  
should be installed  
with the steeper  
flute angle sloping  
15º  
Evaporative Cooler Set-Up  
down towards the entering air side.  
Verify that the stainless steel caps and distribution  
headers are in place. The headers should be located  
over the media towards the entering air side. The caps  
should be placed over the headers.  
Temperature  
Setting  
t2 settings  
t1 settings  
2. Check the Pump Filter  
Check that the pump filter is around the pump inlet.  
3. Fill the Sump and Adjust the Float  
Turn on the water supply and allow the sump tank to  
fill. Adjust the float valve to shut-off the water supply  
when the sump is filled to within 1 in. of the bottom of  
the overflow.  
Evaporative Freeze  
Protection  
Evaporative  
Timer  
4. Break-In the Media  
Open the bleed-off valve completely and saturate  
the media with the blower(s) off for no less than  
20 minutes.  
NOTE  
A jumper will need to be installed in the control  
center to power the evaporative pumps with the  
blower(s) off. Reference the unit’s ladder diagram to  
determine proper terminals.  
5. Check the Flow Rate  
The pumps should provide enough water to saturate  
the media in 45 to 60 seconds. Consult the factory, if  
adequate flow is not achieved.  
6. Adjust the Water Bleed-Off Rate  
The water bleed-off rate is dependent on the water’s  
mineral content. The bleed-off should be adjusted  
based on the media’s mineral deposits after two  
weeks of service.  
7. Set the Optional Auto Drain and Fill  
Set the auto drain, fill timer and temperature settings.  
Temperature is typically set to 45ºF / 7ºC  
Timer settings are: t1: 1.0, 10min  
t2: 0.4, 60h  
8. Put the Unit into Service  
Remove the jumper, and energize the blower(s). Verify  
proper operation.  
IMPORTANT  
Check the media for minerals after two weeks of  
service and adjust the bleed-off rate accordingly.  
Model IG / IGX Make-Up Air  
33  
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4. Close Solenoid  
Start-Up - Water Wizard™ (optional)  
With the pressure set, press the Function key  
L1  
L2  
L3  
for one second to deactivate Flow Test Mode  
and allow the supply solenoid to close.  
5. Check Media  
Function  
Enter  
Up  
Start the cooling cycle and check the media after one  
hour of operation. If the media is continuously dry or if  
too much water is draining from the sump tank, refer  
to Troubleshooting, Water Wizard™.  
Down  
Water Wizard™ User Interface  
Key Function Description  
NOTE  
Steps 6 through 8 are provided to adjust the  
minimum cooling temperature. The minimum cooling  
is preset to the factory recommended 75ºF (24ºC).  
Only adjust if needed.  
1. Open the Solenoid  
Confirm that the manual water supply valve  
is closed. Press and hold the Function key  
for one second. L3 will begin blinking (short on, long  
off), indicating that Flow Test Mode is active and the  
supply solenoid is open.  
NOTE  
The inlet air sensor function overrides and shuts  
down the evaporative cooler if the outside  
temperature falls below the minimum cooling  
temperature.  
WARNING  
Opening the manual supply valve will allow water  
to pass to the media. Be sure the sump is safely  
draining before opening the manual supply valve.  
6. Enter Program Mode  
Press and hold  
NOTE  
the Enter key  
The manual supply valve ships closed and must be  
adjusted for proper performance.  
for three seconds. The  
display will read “Pro”  
when Program Mode is  
2. Set the Water Pressure  
active.  
Program Display  
With the solenoid open, set the supply water  
pressure to the correct setting from the  
7. Adjust the Minimum Cooling  
following tables. Use the manual supply valve to adjust  
the supply pressure. A pressure gauge is provided  
between the manual supply valve and the media.  
Temperature  
While in the  
Program Menu,  
use the Up and  
Down keys to  
navigate the  
NOTE  
The recommended water pressure for the model IGX  
is set based on media width, model IG is set based  
on air volume. A table is provided for each. Be sure  
to refer to the correct table.  
Menu Options  
until “toF” is  
displayed. Press the  
Minimum Cooling  
Temperature Display  
Enter key to access the selected Menu Option setting.  
IGX  
Housing  
Media Width  
(inches)  
Water Pressure  
(in. wg)  
Use the Up and Down keys to adjust the Minimum  
Cooling Temperature as needed. Press the Enter key  
to save the Minimum Cooling Temperature setting and  
return to the Program Menu.  
12  
22  
30  
433  
48  
20  
36  
42  
61  
72  
42  
60  
NOTE  
66  
32  
The Enter key must be pressed to save the new  
minimum cooling temperature.  
96*  
*Multiple media sections. Value represents total media width.  
8. Exit Program Mode  
After ten seconds of idle time the controller will exit  
Program Mode.  
Model IG  
CFM Range  
Water Pressure  
(in. wg)  
800 – 3500  
50  
74  
3501 – 7000  
3. Break-In Media  
Leave the supply solenoid open to saturate and  
break-in media for 20 minutes with the blower off.  
Model IG / IGX Make-Up Air  
34  
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NOTE  
CAUTION  
The Freeze Temperature is preset to the factory  
recommended 45ºF. Steps 9-11 should only  
be completed if the Freeze Temperature needs  
adjustment.  
The sump drain line must be clear and draining to a  
safe location before using Flow Test Mode.  
CAUTION  
Be aware of the water level in the sump tank at all  
times when using the Flow Test Mode.  
NOTE  
The Freeze Temperature is the temperature at which  
the supply solenoid closes and the drain solenoid  
opens to drain the supply line, preventing possible  
freeze damage. A drain solenoid is required for this  
option.  
Program Mode  
Program Mode allows the user to view the Program  
Menu and edit the factory default settings. To access  
Program Mode and view the Program Menu press and  
hold the Enter key for three seconds. While viewing  
the Program Menu press the Up and Down keys to  
scroll through the Menu Options. To view the setting  
of the selected Menu Option, press the Enter key.  
To edit the setting, press the Up or Down key while  
viewing the setting. To save the setting and return to  
the Program Menu, press the Enter key. To return to  
the Program Menu without saving the change, wait  
10 seconds. To exit Program Mode from the Program  
Menu, wait 10 seconds.  
9. Enter Program Mode  
Press and hold  
the Enter key  
for three seconds. The  
display will read “Pro”  
when Program Mode is  
active.  
Program Display  
10. Adjust the Freeze Temperature  
While in Program Mode, use the Up and Down  
keys to navigate  
WARNING  
through the  
Menu Options  
until “Frt” is  
displayed. Press  
Changing the default settings will significantly affect  
performance. Only change a setting after reading  
and understanding this entire manual.  
WARNING  
the Enter key to access  
the selected Menu  
Option setting.  
The Enter key must be pressed to save any changes  
made to a setting.  
Freeze Temperature  
Display  
Use the Up and Down keys to adjust the Freeze  
Temperature setting as needed. Press the Enter key to  
set the Freeze Temperature and return to the Program  
Menu.  
Dry Bulb Temperature  
The dry bulb temperature is visible on the home  
screen. If a number is not visible, wait 15 seconds  
and use the Up and Down keys until a number is  
displayed.  
NOTE  
Wet Bulb Temperature  
To view the Wet Bulb Temperature, simultaneously  
press and hold the Up and Down keys.  
The Enter key must be pressed to save the new  
freeze temperature.  
11. Exit Program Mode  
After ten seconds of idle time the controller will exit  
Program Mode.  
Indicating Lights  
Three indicating lights are located across the top  
of the display to indicate the status of the Water  
Wizard™.  
Operation-Water Wizard™ (optional)  
Light Status  
Drain Mode locks open the drain solenoid  
and drains the supply line between the supply  
solenoid and the media. To activate Drain Mode,  
simultaneously press the Function and Enter keys (L2  
will light). To deactivate Drain Mode and unlock the  
drain solenoid, simultaneously press the Function and  
Enter keys again.  
Blinking  
Long on, short off  
Blinking  
Short on, long off  
Indicating  
Light  
On  
Off  
Call for cooling.  
Outdoor temperature  
lockout.  
Call for No call for  
cooling cooling  
L1  
N/A  
Drain  
solenoid solenoid  
open closed  
Drain  
Supply solenoid open.  
Drain solenoid closed.  
L2  
L3  
N/A  
Flow Test Mode - Activating Flow Test Mode  
opens the supply solenoid and allows water to pass to  
the manual supply valve. To activate Flow Test Mode,  
press and hold the Function key for one second (L3  
will flash). To deactivate Flow Test Mode and allow the  
supply solenoid to close, press and hold the Function  
key again for one second.  
Cooling Cooling  
on off  
Supply solenoid  
locked closed  
Flow test mode active  
Model IG / IGX Make-Up Air  
35  
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Building Pressure Control —  
a variable frequency drive is  
controlled according to input from a  
pressure sensing device.  
BLOWER  
Check Operation - VAV Units  
(optional)  
EXHAUST  
(OPTIONAL)  
SUPPLY  
MAIN VALVES  
HEAT  
NOTE  
DIRTY FILTERS  
(OPTIONAL)  
Turn both knobs to the upper most  
pressure setting. You may have to  
remove the outdoor pressure tap  
tubing. VAV systems should go to  
maximum speed. Set both knobs  
at the lowest setting and the VAV  
systems should go to minimum  
speed.  
70  
75  
65  
60  
55  
80  
85  
Blower Start-Up, Steps 1-5 should be performed  
before the blower is run.  
90  
NOTE  
PHOTOHELIC  
For maintenance issues associated with variable  
frequency drives, consult the drive’s manual  
supplied with the unit. The drives are programmed  
at the factory and should not need any adjustment  
during installation and start-up. For kitchen  
applications, the drive may be located in the kitchen  
or in the unit.  
Building  
Pressure Control  
Reset the correct pressure limits  
before starting the unit.  
Pressure Indicating  
Needle  
Pressure Setting  
Needles  
This picture depicts a typical  
photohelic setting. Typical  
settings are 0.0 in. wg for  
the lower pressure setting  
and 0.10 in. wg for the upper  
pressure setting. The needle  
indicates a negative building  
pressure. During correct  
Variable Volume Operation  
The variable volume option is recommended when  
a building’s exhaust volume may vary. This option  
enables the make-up air volume to track with the  
exhaust volume, providing only the amount of make-  
up air required. Control strategies include 2-speed  
VFD motors and modulating blowers. Before the unit  
is left in service, the variable volume control system  
should be tested.  
operation, the indicating  
needle will remain between  
or near the setting needles.  
Pressure Setting Knobs  
Photohelic Gauge  
External Signal — a variable  
frequency drive is controlled according to input from  
an external 2-10 VDC or 4-20 mA signal (by others).  
2-Speed VFD Motor  
A variable frequency drive (VFD) is used on a single  
speed motor to control air volumes. The VFD is  
factory-programmed for 2 speed operations. It can be  
switched to low or high speed from a remote control  
panel. Turn the fan speed switch on the remote control  
panel to each position and confirm that the fan speed  
adjusts accordingly.  
A 2 VDC or 4 mA signal will send the blower to low  
speed. The blower will go to maximum speed with a  
10 VDC or 20 mA signal.  
Variable Kitchen Control — A variable frequency  
drive is controlled by input from a remote speed  
control. This unit allows automatic adjustment of  
make-up air volumes based on varying cooking loads.  
Modulating  
Potentiometer Control — a variable frequency drive  
is controlled by input from a remote  
BLOWERS  
EXHAUST  
(OPTIONAL)  
speed selector (potentiometer). This  
unit allows easy manual adjustment  
SUPPLY  
MAIN VALVES  
HEAT  
of make-up air volumes. To test  
potentiometer operation, turn the  
potentiometer to the two extremes.  
DIRTY FILTERS  
70  
75  
65  
80  
(OPTIONAL)  
60  
85  
55  
90  
With variable volume, make sure the  
fan goes to maximum and minimum  
speed.  
When the potentiometer is at 0, the  
fan speed will be at its minimum.  
When the potentiometer is at 100,  
the fan will be at its maximum speed.  
Potentiometer  
Control  
Model IG / IGX Make-Up Air  
36  
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Building Pressure Control - a  
modulating spring return actuator  
is used to control the return air  
amounts. The return air damper  
modulates from fully open to fully  
closed based on a signal from a  
remote pressure sensing device.  
Check Operation - Recirculating  
Units (optional)  
BLOWER  
EXHAUST  
(OPTIONAL)  
SUPPLY  
MAIN VALVES  
HEAT  
NOTE  
DIRTY FILTERS  
(OPTIONAL)  
70  
75  
65  
60  
55  
80  
85  
90  
Blower Start-Up, steps 1-5 should be performed  
before the blower is run.  
Turn both knobs to the upper most  
pressure setting. You may have to  
remove the outdoor pressure tap  
tubing. The return air damper should  
close.  
PHOTOHELIC  
Recirculation Operation  
The recirculation operation option is recommended  
when the ventilation equipment provides the primary  
source of heating for the space. Recirculation can  
vary from 100% return air to 100% outside air. Control  
strategies include 2-position and modulating dampers.  
Building  
Pressure Control  
Set both knobs at the lowest setting and the damper  
should open. It may take one to two minutes for the  
damper to reach the desired position.  
Before the unit is left in service, the recirculation  
control system should be tested.  
Reset the correct pressure limits before starting the  
unit.  
This picture shows  
Pressure Indicating Pressure Setting  
2-Position Damper  
A 2-position spring return actuator is used to control  
the return air amounts. The damper moves from open  
to closed. If power is cut to the unit,  
the outdoor air damper will fail to  
close.  
Needle  
Needles  
a typical photohelic  
setting. Typical settings  
are 0.0 in. wg for the  
lower and 0.10 in. wg  
for the upper pressure  
setting. The needle in  
this photo indicates  
a negative building  
pressure. During correct  
operation, the indicating  
needle will remain  
EXHAUST  
BLOWER  
(OPTIONAL)  
SUPPLY  
MAIN VALVES  
HEAT  
RECIRCULATION  
Turn the recirculating switch on  
the remote control panel to each  
position and confirm that the return  
air damper adjusts accordingly. The  
damper actuator may take a few  
minutes to open or close.  
DIRTY FILTERS  
(OPTIONAL)  
70  
75  
65  
60  
55  
80  
85  
90  
Pressure Setting Knobs  
Photohelic Gauge  
2-Position  
Damper Control  
between or near the setting  
needles.  
External Signal - a modulating spring return actuator  
is used to control the return air amounts. Return air  
damper modulates from fully open to fully closed  
based on an external 2-10 VDC or 4-20 mA signal (by  
others).  
Modulating  
Potentiometer Control - a modulating spring return  
actuator is used to control the return air amounts. The  
return air damper modulates from fully open to fully  
closed based on a signal from a remote potentiometer.  
The return air damper will close with a 10 VDC or  
20 mA signal. The return air damper should open with  
a 2 VDC or 4mA signal. The damper actuator may take  
a few minutes to open or close.  
To test potentiometer operation,  
turn the potentiometer to the two  
extremes. Confirm that the return air  
BLOWERS  
EXHAUST  
(OPTIONAL)  
SUPPLY  
MAIN VALVES  
HEAT  
damper fully opens and fully closes.  
When the potentiometer is at 0, the  
return air damper will open. When the  
DIRTY FILTERS  
70  
75  
65  
80  
(OPTIONAL)  
60  
85  
55  
90  
potentiometer is at 100, the return  
air damper will close. The damper  
actuator may take a few minutes to  
open or close.  
Potentiometer  
Control  
Model IG / IGX Make-Up Air  
37  
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4. Ignition Controller (IC1) Sequence of Operation  
Sequence of Operation  
2:1 Staged Sequence  
The N.O. contact on air proving switch (PS2) is open  
The ignition controller (IC1) energizes the  
combustion blower relay (CR)  
N.O. contact on combustion blower relay (CR)  
closes  
Power passes to and energizes the combustion  
blower (CM)  
1. Exhaust Fan Contact (S1) Manually Closed  
(optional)  
Power passes through N.C. contact on exhaust fan  
overload (ST2 OL), which is closed if exhaust fan  
(M2) has not overloaded  
Power passes to exhaust fan starter (ST2)  
N.O. contact on exhaust fan starter (ST2) is  
energized and closed  
The N.O. contact on air proving switch (PS2) closes  
The ignition controller (IC1) begins a 15 second  
pre-purge  
Power passes to and energizes exhaust fan (M2)  
The high fire relay (RT3) is energized and the N.O.  
contact on high fire relay (RT3) closes  
2. Supply Fan Contact (S2) Manually Closed  
The main gas valve (MV) fully opens (100%)  
Igniter begins sparking  
10 second trial for ignition begins  
The furnace will light at high fire (100%)  
When the flame is detected, the igniter stops  
sparking  
The furnace will remain at high fire (100%) for at  
least 10 seconds  
High fire contact (RT3) will open  
Furnace stages to maintain the discharge air  
Power passes through N.C. field-supplied fire  
contact (FSC)  
Power passes through optional N.O. contact on  
exhaust fan starter (ST2), which is closed when the  
optional exhaust starter (ST2) is activated  
Power passes through N.C. contact on supply  
starter overload (ST1 OL), which is closed if the  
supply fan has not overloaded  
Power passes through N.C. contact on optional  
freeze protection timer (RT4), which is closed if the  
temperature has remained above the set point  
temperature set point (SC1)  
Power passes to and energizes optional inlet  
damper (D1), which opens  
5. High Fire – Low Fire Sequence of Operation  
The furnace lights at high fire (100%) and remains  
at high fire for 10 seconds  
Power passes through optional damper limit switch  
(DL1), which is energized and closed if the optional  
inlet damper is open. It may take several minutes  
for the damper to fully open and for the damper  
limit switch to close  
If the discharge temperature is above the discharge  
air sensor (TS2) set point, the N.O. furnace stage 2  
controller contact (SC2), will open and the furnace  
will go to low fire (50%)  
If the furnace is at low fire (50%) and the discharge  
temperature is above the discharge air sensor  
(TS2) set point, the furnace stage 1 contact (SC1)  
will open and the furnace will shut down  
If the furnace is at low fire (50%) and the discharge  
temperature is below the discharge air sensor (TS2)  
set point, the furnace stage 2 contact (SC2) will  
close and the furnace will go to high fire  
Power passes to and energizes fan relay (RF)  
Power passes through N.O. contact on fan relay  
(RF), which is closed once the fan relay (RF) is  
activated  
Power passes to and energizes starter relay (ST1)  
N.O. contact on supply fan starter (ST1) is  
energized and closed  
Supply fan (M1) starts  
3. Heat Contact (S4) Manually Closed  
6. Optional Evaporative Cooling Contact (S4)  
Closed*  
Power passes through N.O. fan relay (RF), which is  
energized and closed if the supply fan (M1) is on  
N.O. contact on fan relay (RF) is energized and  
closed  
Power passes through N.C. contact on optional  
inlet air sensor (TS4), which is closed if inlet air  
temperature is below the set point  
Power passes to and energizes the heat relay (RH)  
N.O. contact on heat relay (RH) closes  
Power passes through N.O. contact on optional  
inlet air sensor (TS4), which is energized and  
closed if the inlet air temperature is above the set  
point  
Power passes to and energizes cool relay (RC)  
N.O. contact on cool relay (RC) is energized and  
24 VAC is supplied to stage controller (SC1)  
If the discharge temperature is less than the set  
point on the discharge air sensor (TS2) and the  
high temperature limit control (HLC1) has not  
been tripped, the N.O. contact for furnace stage  
controller will close  
closed  
Power passes to evaporative cooling pump (P1)  
*If DX or chilled water coils are used rather than an  
evaporative cooler, the cooling sequence of operation  
will depend on the coil controls. Cooling coil controls are  
supplied by others.  
Power will be supplied to the ignition controller  
(IC1), which will begin its sequence of operation  
Model IG / IGX Make-Up Air  
38  
®
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amplifier (AMP) sends a call for heating to the  
ignition controller (IC1)  
Sequence of Operation  
2:1 Modulation Sequence  
4. Ignition Controller (IC1) Sequence of Operation  
The N.O. contact on air proving switch (PS2) is open  
1. Exhaust Fan Contact (S1) Manually Closed  
(optional)  
The ignition controller (IC1) energizes the  
combustion blower relay (CR)  
N.O. contact on combustion blower relay (CR)  
closes  
Power passes to and energizes the combustion  
blower (CM)  
Power passes through N.C. contact on exhaust fan  
overload (ST2 OL), which is closed if exhaust fan  
(M2) has not overloaded  
Power passes to exhaust fan starter (ST2)  
N.O. contact on exhaust fan starter (ST2) is  
energized and closed  
Power passes to and energizes exhaust fan (M2)  
The N.O. contact on air proving switch (PS2) closes  
The ignition controller (IC1) begins a 15 second  
pre-purge  
2. Supply Fan Contact (S2) Manually Closed  
The high fire relay (RT3) is energized and the N.O.  
contact on high fire relay (RT3) closes  
The main gas valve (MV) fully opens (100%) and the  
modulating gas valve (MOD) opens to high fire  
Igniter begins sparking  
10 second trial for ignition begins  
The furnace will light at high fire (100%)  
When the flame is detected, the igniter stops  
sparking  
The furnace will remain at high fire (100%) for at  
least 10 seconds  
High fire contact (RT3) will open  
Furnace modulates to maintain the temperature  
Power passes through N.C. field-supplied fire  
contact (FSC)  
Power passes through optional N.O. contact on  
exhaust fan starter (ST2), which is closed when the  
optional exhaust starter (ST2) is activated  
Power passes through N.C. contact on supply  
starter overload (ST1 OL), which is closed if the  
supply fan has not overloaded  
Power passes through N.C. contact on optional  
freeze protection timer (RT4), which is closed if the  
temperature has remained above the set point  
Power passes to and energizes optional inlet  
damper (D1), which opens  
Power passes through optional damper limit switch  
(DL1), which is energized and closed if the optional  
inlet damper is open. It may take several minutes  
for the damper to fully open and for the damper  
limit switch to close  
selector (TS3) set point  
5. High Fire – Low Fire Sequence of Operation  
The furnace lights at and remains at high fire  
(100%) for 10 seconds  
If the discharge temperature sensor (TS2) reading  
is above the temperature selector (TS3) set point,  
and furnace is not at low fire, the amplifier will  
adjust the modulating gas valve (MOD) down until  
the discharge temperature sensor (TS2) reading  
equals the temperature selector (TS3) setting  
If the discharge temperature sensor (TS2) reading  
is below the temperature selector (TS3) set point,  
and the furnace is not at high fire, the amplifier will  
adjust the modulating gas valve (MOD) up until the  
discharge temperature sensor (TS2) reading equals  
the temperature selector (TS3) setting  
If the furnace is at low fire and the discharge  
temperature sensor (TS2) reading is above the  
temperature selector (TS3) set point, the amplifier  
will end the call for heat and the ignition controller  
(IC1) will shut down the furnace  
Power passes to and energizes fan relay (RF)  
Power passes through N.O. contact on fan relay  
(RF), which is closed once the fan relay (RF) is  
activated  
Power passes to and energizes starter relay (ST1)  
N.O. contact on supply fan starter (ST1) is  
energized and closed  
Supply fan (M1) starts  
3. Heat Contact (S4) Manually Closed  
Power passes through N.O. contact on fan relay  
(RF), which is energized and closed if the supply  
fan (M1) is on  
Power passes through the N.C. contact on optional  
inlet air sensor (TS4), which is closed if inlet air  
temperature is below set point  
Power passes to and energizes the heat relay (RH)  
6. Optional Evaporative Cooling Contact (S4)  
Closed*  
Power passes to N.C. contact on high temperature  
limit control (HLC1), which remains closed if it has  
not been tripped  
N.O. contact on fan relay (RF) is energized and  
closed  
N.O. contact on heat relay (RH) closes  
24 VAC is supplied to ignition controller (IC1) and  
Power passes through N.O. contact on optional  
inlet air sensor (TS4), which is energized and  
closed if the inlet air temperature is above the set  
point  
amplifier (AMP)  
If the discharge air sensor (TS2) reading is less  
than the temperature selector (TS3) setting, the  
Power passes to and energizes cool relay (RC)  
Model IG / IGX Make-Up Air  
39  
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Sequence of Operation  
Operation  
2:1 Modulation Sequence, continued  
4:1 Modulation and  
8:1 Staged Controller  
N.O. contact on cool relay (RC) is energized and  
closed  
Power passes to evaporative cooling pump (P1)  
L1  
L2  
L3  
*If DX or chilled water coils are used rather than an  
evaporative cooler, the cooling sequence of operation  
will depend on the coil controls. Cooling coil controls are  
supplied by others.  
Function  
Enter  
Up  
Down  
Water Wizard™ User Interface  
Key Function Description  
Program Mode  
Program Mode allows the user to view the Program  
Menu and edit the factory default settings. To access  
Program Mode and view the Setpoints Menu, press  
and hold the Function key for three seconds. While  
viewing the Setpoints Menu, press the Up or Down  
key to scroll through the menu options. To view the  
setting of the selected menu option, press the Enter  
key. To edit the setting, press the Up or Down key  
while viewing the setting. To save the setting and  
return to the Setpoints Menu press the Enter key.  
To return to the Setpoints Menu without saving the  
change, wait 15 seconds. To exit Program Mode from  
the Setpoints Menu, wait 15 seconds.  
WARNING  
Changing the default settings will significantly affect  
performance. Only change a setting after reading  
and understanding this entire manual.  
NOTE  
The Enter key must be pressed to save any changes  
made to a setting.  
Inlet Air Sensor (iAS)  
The inlet air sensor monitors the temperature of the  
inlet air. If the inlet air is above the sensor’s set point,  
the inlet air sensor shuts off the furnace and continues  
to supply the warm outside air. The inlet air sensor is  
preset to the factory recommended 65ºF for 8:1 and  
60ºF for 4:1.  
Discharge Air Temperature (dtS)  
The discharge air temperature setting is the  
temperature that the unit will discharge. The discharge  
air temperature is preset to the factory recommended  
70ºF. The actual discharge air temperature is the  
default display.  
Outside Air Temperature (OAt)  
To temporarily display the outside air temperature, use  
the Up or Down key until the display reads “OAt,” then  
press the Enter key.  
Model IG / IGX Make-Up Air  
40  
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Program Revision Number  
Sequence of Operation  
To access the program revision number from the default  
display, press the Up or Down key until the display reads  
F##, J## or I##. The two numbers following the letter  
indicate the revision number. For example, F12 indicates  
program F, revision twelve.  
4:1 Electronic Modulation  
1. Exhaust Fan Contact (S1) Manually Closed  
(optional)  
Power passes through N.C. contact on exhaust fan  
overload (ST2 OL), which is closed if exhaust fan  
(M2) has not overloaded  
Optional Room Override (ROt)  
When the room override function is triggered, the  
discharge air temperature (70ºF default) is temporarily  
changed to the room override setting (90ºF default).  
When the room override function is released the  
discharge air temperature returns to the default  
temperature.  
Power passes to exhaust fan starter (ST2)  
N.O. contact on exhaust fan starter (ST2) is  
energized and closed  
Power passes to and energizes exhaust fan (M2)  
2. Supply Fan Contact (S2) Manually Closed  
Indicating Lights  
Three indicating lights are located across the top of  
the display to indicate the status of the furnace.  
Power passes through N.C. field-supplied fire  
contact (FSC)  
Power passes through optional N.O. contact on  
exhaust fan starter (ST2), which is closed when the  
optional exhaust starter (ST2) is activated  
4:1 Electronic Modulation  
Light  
L1  
On  
Call for Heat  
Off  
Blinking  
High fire  
Power passes through N.C. contact on supply  
starter overload (ST1 OL), which is closed if the  
supply fan has not overloaded  
Power passes through N.C. contact on optional  
freeze protection timer (RT4), which is closed if the  
temperature has remained above the set point  
No call for heat  
Call for heat  
No call for heat  
L2  
L3  
sent to ignition sent to ignition  
controller controller  
Combustion fan Combustion fan  
high speed low speed  
High fire  
High fire  
Power passes to and energizes optional inlet  
damper (D1), which opens  
8:1 Staged Control  
(Single Furnace Units)  
Power passes through optional damper limit switch  
(DL1), which is energized and closed if the optional  
inlet damper is open. It may take several minutes  
for the damper to fully open and for the damper  
limit switch to close  
Light  
L1  
On  
Call for heat  
n/a  
Off  
No call for heat  
n/a  
Blinking  
N/A  
L2  
High fire  
n/a  
L3  
Burner interlock  
n/a  
8:1 Staged Control  
(Multi Furnace Units)  
Power passes to and energizes fan relay (RF)  
Power passes through N.O. contact on fan relay  
(RF), which is closed once the fan relay (RF) is  
activated  
Power passes to and energizes starter relay (ST1)  
N.O. contact on supply fan starter (ST1) is  
Light  
L1  
On  
n/a  
n/a  
Off  
n/a  
n/a  
Blinking  
n/a  
L2  
Alarm  
Saving new  
setting  
L3  
Program Mode  
n/a  
energized and closed  
Supply fan (M1) starts  
3. Heat Contact (S4) Manually Closed  
Power passes through N.O. contact on fan relay  
(RF), which is energized and closed if the supply  
fan (M1) is on  
Power passes to and energizes the heat relay (RH)  
N.O. contact on heat relay (RH) closes  
Power passes to N.C. contact on high temperature  
limit control (HLC1), which remains closed if it has  
not been tripped  
24 VAC is supplied to ignition controller (IC1)  
The modulating controller (SC1) compares the  
inlet air temperature to the inlet air set point (iAS,  
FX Program Menu). If the inlet air temperature is  
below the set point, the modulating controller (SC1)  
closes N.O. contact (FUR 1) and sends a call for  
heat to the ignition controller (IC1)  
Model IG / IGX Make-Up Air  
41  
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Sequence of Operation  
4:1 Electronic Modulation, continued  
Power passes to and energizes cool relay (RC)  
N.O. contact on cool relay (RC) is energized and  
closed  
4. Ignition Controller (IC1) Sequence of Operation  
The N.O. contact on air proving switch (PS2) is open  
The ignition controller (IC1) energizes the induction  
Power passes to evaporative cooling pump (P1)  
relay (IR)  
*If DX or chilled water coils are used rather than an  
evaporative cooler, the cooling sequence of operation  
will depend on the coil controls. Cooling coil controls are  
supplied by others.  
N.O. contact on induction relay (IR) closes  
Power passes to and energizes the combustion  
blower (CM), sending it to high speed  
The N.O. contact on air proving switch (PS2) and  
high pressure switch (PS5) closes  
The ignition controller (IC1) begins a 15 second  
pre-purge  
The main gas valve (MV) fully opens (100%) and the  
modulating gas valve (MOD) opens to high fire  
Igniter begins sparking  
10 second trial for ignition begins  
The furnace will light at high fire (100%)  
When the flame is detected, the igniter stops  
sparking  
The furnace will remain at high fire (100%) for 30  
seconds  
The modulation controller (SC1) will adjust the  
modulating gas valve (MOD) and the combustion  
blower (CM) as needed between low and high fire  
The modulating controller (SC1) will monitor the  
high pressure switch (PS5) and run the furnace at  
low fire if the high pressure switch is not satisfied  
5. High Fire – Low Fire Sequence of Operation  
The furnace lights at and remains at high fire  
(100%) for 30 seconds  
If the discharge temperature sensor (TS2) reading  
is above the discharge temperature setting (dtS,  
FX Program Menu), and the furnace is not at low  
fire, the modulating controller (SC1) will adjust  
the modulating gas valve (MOD) down until the  
discharge temperature sensor (TS2) reading  
equals the discharge temperature setting (dtS, FX  
Program Menu)  
If the discharge temperature sensor (TS2) reading  
is below the discharge temperature setting (dtS,  
FX Program Menu), and the furnace is not at high  
fire, the modulating controller (SC1) will adjust the  
modulating gas valve (MOD) up until the discharge  
temperature sensor (TS2) reading equals the  
discharge temperature setting (dtS, FX Program  
Menu)  
6. Optional Evaporative Cooling Contact (S4)  
Closed*  
N.O. contact on fan relay (RF) is energized and  
closed  
Power passes through N.O. contact on inlet air  
sensor (TS4), which is energized and closed if the  
inlet air temperature is above the set point  
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N.O. contact on combustion blower relay (CR)  
closes  
Power passes to and energizes the combustion  
Sequence of Operation  
8:1 Staged Control  
blower (CM)  
1. Exhaust Fan Contact (S1) Manually Closed  
(optional)  
The N.O. contact on air proving switch (PS2) closes  
Power passes to and energizes air proving switch  
relay (R9)  
N.O. contacts on air proving switch (R9) closes  
The ignition controller (IC) completes a 30 second  
pre-purge  
Power passes through N.C. contact on exhaust fan  
overload (ST2 OL), which is closed if exhaust fan  
(M2) has not overloaded  
Power passes to exhaust fan starter (ST2)  
N.O. contact on exhaust fan starter (ST2) is  
energized and closed  
Power passes to and energizes exhaust fan (M2)  
The main gas valve (MV) fully opens (100%)  
Igniter begins sparking  
10 second trial for ignition begins  
The furnace will light  
The stage controller (SC1) will choose which stage  
to light the furnace at based on the discharge air  
temperature setting (dtS, FX Program Menu) and  
the outside air temperature (TS1)  
When the flame is detected, the igniter stops  
sparking  
The furnace will remain at high fire (100%) for 20  
seconds  
The stage controller (SC1) will stage the main gas  
valves (MV#) as needed between low fire, high fire  
and off  
If the furnace is at low fire and the discharge  
temperature sensor (TS2) reading remains above  
the discharge air temperature setting (dtS, FX  
Program Menu) for more than six minutes, the  
furnace will shut down  
2. Supply Fan Contact (S2) Manually Closed  
Power passes through N.C. field-supplied fire  
contact (FSC)  
Power passes through optional N.O. contact on  
exhaust fan starter (ST2), which is closed when the  
optional exhaust starter (ST2) is activated  
Power passes through N.C. contact on supply  
starter overload (ST1 OL), which is closed if the  
supply fan has not overloaded  
Power passes through N.C. contact on optional  
freeze protection timer (RT4), which is closed if the  
temperature has remained above the set point  
Power passes to and energizes optional inlet  
damper (D1), which opens  
Power passes through optional damper limit switch  
(DL1), which is energized and closed if the optional  
inlet damper is open. It may take several minutes  
for the damper to fully open and for the damper  
limit switch to close  
5. Staging Control Sequence of Operation  
Power passes to and energizes fan relay (RF)  
If the discharge temperature (TS2) is below the  
discharge air temperature set point (dtS, FX  
Program Menu), the furnace will stage up  
If the discharge temperature (TS2) is above the  
discharge air temperature set point (dtS, FX  
Program Menu), the furnace will stage down  
If the discharge temperature (TS2) is above the  
discharge air temperature set point (dtS, FX  
Program Menu) and the furnace is at low fire, the  
furnace will shut off  
If the furnace is at high fire and the discharge air  
temperature setting (dtS, FX Program Menu) is not  
satisfied, the furnace will remain at high fire  
Power passes through N.O. contact on fan relay  
(RF), which is closed once the fan relay (RF) is  
activated  
Power passes to and energizes starter relay (ST1)  
N.O. contact on supply fan starter (ST1) is  
energized and closed  
Supply fan (M1) starts  
3. Heat Contact (S4) Manually Closed  
Power passes through N.O. contact on fan relay  
(RF), which is energized and closed if the supply  
fan (M1) is on  
Power passes to and energizes the heat relay (RH)  
N.O. contact on heat relay (RH) closes  
If the furnace is at low fire and the discharge air  
temperature setting (dtS, FX Program Menu) is  
satisfied, the furnace will shut off  
The stage controller (SC1) compares the inlet  
air temperature to the inlet air set point (iAS, FX  
Program Menu). If the inlet air temperature is below  
the discharge air setting (dtS, FX Program Menu),  
the stage controller sends a call for heat to the  
ignition controller (IC1)  
6. Optional Evaporative Cooling Contact (S4)  
Closed*  
N.O. contact on fan relay (RF) is energized and  
closed  
Power passes through N.O. contact on optional  
inlet air sensor (TS4), which is energized and  
closed if the inlet air temperature is above the set  
point  
4. Ignition Controller (IC1) Sequence of Operation  
The N.O. contact on air proving switch (PS2) is  
open  
The stage controller (SC1) energizes the  
Power passes to and energizes cool relay (RC)  
combustion blower relay (CR)  
Model IG / IGX Make-Up Air  
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Sequence of Operation  
Operation and Errors -  
Ignition Controller  
8:1 Staged Control, continued  
N.O. contact on cool relay (RC) is energized and  
closed  
Power passes to evaporative cooling pump (P1)  
NOTE  
The green LED light indicates NORMAL operation  
while the red LED light indicates an ERROR  
operation.  
*If DX or chilled water coils are used rather than an  
evaporative cooler, the cooling sequence of operation  
will depend on the coil controls. Cooling coil controls are  
supplied by others.  
This controller is found only in the furnace control  
center. It has an LED indicator light on the top right  
of the controller that  
will flash GREEN for  
NORMAL operation or  
RED for an ERROR. Some  
furnace configurations  
have two of these  
controllers.  
The following are the green LED codes of operation:  
GREEN LED Indications - NORMAL OPERATION  
Flash Code  
Flash Code Indication  
Steady on  
Flame detected, main burner on  
Controller is sparking  
0.1 second on/off  
0.5 second on/off  
0.5 second on/4.5 second off  
Purge or inter-purge time  
Retry or recycle time  
The following are the red LED codes of error:  
RED LED Indications - ERROR OPERATION  
Flash Code  
Flash Code Indication  
No flame in trial time error  
Flame sense circuit error  
Valve circuit error  
Blinks 1 time  
Blinks 2 times  
Blinks 3 times  
Blinks 4 times  
Blinks 6 times  
Blinks 7 times  
Steady on  
Flame loss error  
Airflow error  
Ground or internal error  
Line voltage/frequency error  
Model IG / IGX Make-Up Air  
44  
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Option EC-4  
(Differential Enthalpy Control)  
Operation - Economizer  
This option uses one enthalpy sensor, eld-installed in  
the inlet of the unit. A second enthalpy sensor is field-  
installed in the return air duct. A dry bulb temperature  
sensor is factory-installed in the discharge of the unit.  
NOTE  
Only models IG-HV and IGX-HV with options EC-1,  
2, 3 or 4 use an economizer.  
After a call for cooling the economizer compares  
the outdoor and return air enthalpies. If the outdoor  
air enthalpy is greater than the return air enthalpy,  
the economizer sends the dampers to the minimum  
outside air position and sends a call for mechanical  
cooling. If the outside enthalpy is less than the  
return air enthalpy, the economizer will modulate the  
Option EC-1  
(Outside Air Temperature Reference)  
This option uses one dry bulb temperature sensor  
field-installed in the inlet of the unit. A second dry  
bulb temperature sensor is factory-installed in the  
discharge of the unit.  
After a call for cooling, the outside air temperature is  
compared to the economizer set point. If the outside  
air temperature is above the economizer set point,  
the economizer sends the dampers to the minimum  
outside air position and calls for mechanical cooling. If  
the outside air temperature is between the economizer  
dampers to achieve a 55  
If the outside enthalpy is less than the return air  
temperature, but a 55 F mixed air temperature cannot  
°F mixed air temperature.  
°
be achieved, the programmable room thermostat may  
call for mechanical cooling.  
set point and 55  
to the 100% outside air position. If the outside air  
is less than 55 F, the economizer modulates the  
°F, the economizer sends the dampers  
°
dampers to achieve a 55°F mixed air temperature.  
Option EC-2  
(Outside Air Enthalpy Reference)  
This option uses one enthalpy sensor field-installed in  
the inlet of the unit. A dry bulb temperature sensor is  
installed in the discharge of the unit.  
After a call for cooling, the outside air enthalpy is  
compared to the field-adjustable enthalpy changeover  
set point. If the outside air enthalpy is less than the  
set point, the dampers will modulate to provide a 55  
°F  
mixed air temperature. If the outside air enthalpy is  
greater than the set point, the economizer sends the  
damper to the minimum outside air position and sends  
a call for mechanical cooling.  
Option EC-3  
(Differential Temperature Control)  
This option uses one dry bulb temperature sensor  
field-installed in the inlet of the unit. A second dry bulb  
temperature sensor is field-installed in the return air  
duct. A third dry bulb temperature sensor is factory-  
installed in the discharge of the unit.  
After a call for cooling the economizer compares the  
outdoor and return air temperatures. If the outdoor  
air temperature is greater than the return air dry bulb  
temperature, the economizer sends the dampers to  
the minimum outside air position and sends a call for  
mechanical cooling. If the outside air temperature is  
less than the return air temperature, the economizer  
will modulate the dampers to achieve a 55  
air temperature. If the outside air temperature is less  
than the return air temperature, but a 55 F mixed air  
°F mixed  
°
temperature cannot be achieved, the programmable  
room thermostat may call for mechanical cooling.  
Model IG / IGX Make-Up Air  
45  
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Troubleshooting  
Blower Does Not Operate  
No  
Proper supply power at  
main disconnect  
Check Main Voltage  
(See Blower Start-Up Step #1)  
Main Disconnect (DS1) Off  
(Turn Main Disconnect DS1 On)  
Primary Fuses Blown  
Yes  
(Replace Fuses)  
No  
No  
No  
No  
No  
24 VAC between  
terminals R and X?  
Main Transformer (TR1) Defective  
Yes  
(Replace Transformer)  
24 VAC between  
terminals G and X?  
Supply Switch (S2) Off  
(Turn Supply Switch (S2) On)  
Fire system contact (FSC) tripped/not installed  
(Correct/Replace)  
Yes  
24 VAC across  
terminals 3 and X?  
Supply Fan Overload (ST1 OL) Tripped  
(Reset and check motor amps, reference Blower Start-Up #4)  
Optional Exhaust Fan Interlocks (ST2-ST5) Open  
(Correct/Replace)  
Yes  
24 VAC across  
terminals 4 and X?  
Yes  
(Optional) Freeze Protection (RT4) Tripped  
(Reset)  
24 VAC across A2 and A1 on  
supply contactor (ST1)  
(Optional) Damper Limit Switch (DL1) Holding  
(Wait for actuator to open fully or adjust limit switch)  
(Optional) Damper Limit Switch Jumper Missing  
(Install jumper, reference the unit ladder diagram for terminals)  
Fan Relay (RF) is not energized  
Yes  
(Check for loose connection) (Repair or replace relay)  
Broken Fan Belt  
(Replace - Reference V-Belt drives in the Maintenance section)  
Defective motor or capacitor  
(Repair/Replace)  
Blown Motor Fuse  
(Replace)  
One or more legs of 3 phase is out  
(Restore missing legs)  
At this time the supply contactor (ST1) should pull in,  
passing power to the supply motor  
and the blower should start.  
Model IG / IGX Make-Up Air  
46  
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Troubleshooting  
Motor Over Amps  
Yes  
Yes  
No  
Air volume too high?  
Adjust drives or increase external  
static pressure as needed.  
No  
(Reference Blower Start-Up Step #5)  
Actual static pressure  
lower than design?  
No  
Adjust drives to reduce blower RPM.  
(Reference Blower Start-Up Step #5)  
Blower rotation correct?  
Yes  
Reverse blower rotation.  
(Reference Blower Start-Up Step #2)  
No  
Motor voltage correct?  
Yes  
Provide proper power supply.  
(Reference Blower Start-Up Step #1)  
Yes  
Yes  
Motor horsepower too low?  
No  
Resize motor.  
Shorted windings in motor?  
Yes  
Replace motor.  
Everything is working  
properly, consult factory.  
Model IG / IGX Make-Up Air  
47  
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Troubleshooting  
Insufficient Airflow  
Yes  
Yes  
Yes  
Yes  
Yes  
Yes  
Damper(s) not fully opened?  
No  
Adjust damper linkage(s), or replace faulty actuator(s).  
(Damper actuators may take a few minutes to open)  
System static losses too high?  
No  
Reduce losses by improving ductwork.  
Blower speed too low?  
No  
Adjust drives as needed.  
(Reference Blower Start-Up – Step #5)  
Filters dirty or clogged?  
No  
Clean or replace filters.  
(Reference Filters in the Maintenance section)  
Leaks in ductwork?  
No  
Repair leaks.  
Belt slipping?  
Yes  
Replace or tighten belt.  
(Reference V-Belt Drives in the Maintenance section)  
Everything is working properly,  
consult factory.  
Too Much Airflow  
Yes  
Yes  
Yes  
Blower speed too high?  
No  
Adjust drives as needed.  
(Reference Blower Start-Up – Step #5)  
Filters not in place?  
No  
Install filters.  
Insufficient external static  
pressure?  
No  
Increase external static pressure.  
Everything is working properly,  
consult factory.  
Model IG / IGX Make-Up Air  
48  
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Troubleshooting  
Excessive Noise or Vibration  
Yes  
Belts worn or loose?  
Replace worn belts or tighten loose belts.  
(Reference V-Belt Drives in the Maintenance section)  
No  
No  
Sheaves aligned?  
Align sheaves.  
(Reference V-Belt Drives in the Maintenance section)  
Yes  
Yes  
Yes  
Yes  
Wheel(s) unbalanced?  
Clean and/or balance wheel(s).  
No  
Bearings worn or need  
lubrication?  
Replace worn bearings or lubricate bearings as needed.  
(Reference Bearings in the Maintenance section)  
No  
Wheel(s) rubbing on inlet?  
Adjust wheel(s) or inlet.  
No  
At this time noise and vibration should  
be at acceptable levels.  
Model IG / IGX Make-Up Air  
49  
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Troubleshooting  
Single or 2:1 Stage Furnace Will Not Light  
No  
24 VAC across R and X?  
Main disconnect (DS1) open or defective  
Close, repair or replace  
Yes  
Main transformer (TR1) fault  
Replace main transformer  
No  
24 VAC across W1 and X?  
Yes  
Heat Switch (S4) open  
(Turn Heat Switch (S4) on)  
No  
24 VAC across 22 and 21?  
Yes  
Heating Transformer (TR2) Fault  
Replace heating transformer  
No  
24 VAC across 24 VAC and  
21 on SC1 controller?  
Optional inlet air sensor (TS4) open  
Adjust setting. Reference Blower Start-Up, Step #6  
Heat relay (RH) is not energized  
Yes  
24 VAC across A and 21?  
Yes  
Check for loose connections. Repair or replace heat relay (RH)  
No  
Discharge air selector (TS2) improperly set or faulty  
Adjust setting (see Staged Start-Up) or replace sensor  
Furnace stage one contact (SC1) defective (stage only)  
Replace furnace stage one contact  
Yes  
Yes  
Yes  
Yes  
High limit (HLC1) open?  
No  
Discharge temperature was above high limit setting.  
Wait for high limit to cool and reset.  
Ignition controller (IC#)  
red LED  
blinks 7 times or is on  
No  
Ignition controller (IC1) failed.  
(Replace ignition controller)  
Ignition controller (IC#)  
red LED  
blinks 6 times  
Combustion blower (CM) not functioning  
Replace combustion blower or relay (CR)  
Air proving switch (PS2) defective.  
Replace air proving switch  
No  
Ignition controller (IC#)  
red LED blinks  
1 time, 2 times or 4 times  
Improper manifold pressure  
Set high and low manifold pressure (refer to Single Stage or  
2:1 Staged Control Start-Up section)  
Yes  
Faulty spark rod or spark gap does not equal 1/8 inch  
Everything is working  
properly, consult factory.  
Replace spark rod or adjust gap to 18 inch  
Model IG / IGX Make-Up Air  
50  
®
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Troubleshooting  
2:1 Modulating Furnace Will Not Light  
No  
24 VAC across R and X?  
Main disconnect (DS1) open or defective  
Close, repair or replace  
Yes  
Main transformer (TR1) fault  
Replace main transformer  
No  
24 VAC across W1 and X?  
Yes  
Heat switch (S4) open or not wired  
Close or replace heat switch (S4)  
No  
24 VAC across S and T?  
Yes  
Heat transformer (TR5) fault  
Replace heating transformer  
Discharge temperature was above high limit control (HLC1)  
Wait for high limit to cool and reset.  
No  
24 VAC across C and T?  
Optional inlet air sensor contact (TS4 open)  
Adjust setting reference Blower Start-Up, Step #6  
Heat relay (RH) is not energized  
Yes  
Check for loose connections. Repair or replace heat relay (RH)  
No  
24 VAC across A and T?  
Yes  
Discharge air selector (TS3) improperly set or faulty  
Adjust setting (see staged start-up) or replace sensor  
Ignition controller (IC#)  
Yes  
red LED  
blinks 7 times or is on  
No  
Ignition controller (IC1) failed  
(Replace ignition controller)  
Ignition controller (IC#)  
Yes  
red LED  
blinks 6 times  
Combustion blower (CM) not functioning  
Replace combustion blower or relay (CM)  
Air proving switch (PS2) defective  
Replace air proving switch  
No  
Ignition controller (IC#)  
Yes  
red LED blinks  
1 time, 2 times or 4 times  
Improper manifold pressure  
Set high and low manifold pressure (refer to the 2:1 Electronic  
Modulation Start-Up section)  
Yes  
Faulty spark rod or spark gap does not equal 1/8 inch  
Everything is working  
properly, consult factory.  
Replace spark rod or adjust gap to 18 inch  
Model IG / IGX Make-Up Air  
51  
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Troubleshooting  
4:1 Modulating Furnace Will Not Light  
No  
24 VAC across R and X?  
Main disconnect (DS1) open or defective  
Close, repair or replace  
Yes  
Main transformer (TR1) fault  
Replace main transformer  
No  
24 VAC across W1 and X?  
Yes  
Heat switch (S4) open or not wired  
Close or replace heat switch (S4)  
No  
24 VAC across 22 and 21?  
Yes  
Heat transformer (TR2) fault  
Replace heating transformer  
No  
Yes  
Yes  
Yes  
N.O. contact on  
heat relay (RH) closed?  
Yes  
Heat relay (RH) is not energized  
Check for loose connections. Repair or replace heat relay (RH)  
DT1 displayed  
on furnace controller (SC1)?  
No  
Discharge air sensor (TS2) not wired or defective  
Wire or replace discharge air sensor (TS2)  
OT1 displayed  
on furnace controller (SC1)?  
No  
Outdoor air sensor (TS1) not wired or defective  
Wire or replace outdoor temperature sensor (TS1)  
Blank screen  
on furnace controller (SC1)?  
No  
Furnace controller (SC1) defective or not powered  
Replace or wire furnace controller (SC1)  
No  
24 VAC across  
terminals S and T?  
Discharge temperature was above high limit control (HLC1)  
Wait for high limit to cool and reset  
Yes  
Inlet air sensor contact open  
Adjust inlet air sensor setting (refer to 4:1 Modulation Start-Up section)  
Furnace controller (SC1) defective  
Replace furnace controller (SC1)  
Continues on next page...  
Model IG / IGX Make-Up Air  
52  
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Troubleshooting  
4:1 Modulating Furnace Will Not Light  
...continued from previous page  
Yes  
High limit switch (HLC#) open?  
No  
Discharge temperature was above high limit setting  
Let cool, then reset high limit.  
Ignition controller (IC#)  
Yes  
red LED blinks  
7 times or is on  
No  
Ignition controller(s) (IC#) failed  
Replace faulty ignition controller(s)  
Yes  
No  
No  
No  
Yes  
Ignition controller (IC#)  
red LED blinks 6 times  
Pressure switch (PS2) failure  
Repair or replace pressure switch (PS2)  
Combustion blower (CM) not functioning  
Replace fusing (FU7), combustion blower or relay (CM)  
No  
24 VAC between terminals  
1 and 2 on the Amplifier (AMP)  
Yes  
Secondary transformer (TR6) defective  
Replace secondary transformer (TR6)  
10 VDC between terminals  
5 and 6 on the Amplifier (AMP)  
Yes  
Furnace controller (SC1) defective  
Replace furnace controller (SC1)  
24 VDC between terminals  
3 and 4 on the Amplifier (AMP)  
Yes  
Amplifier (AMP) defective  
Replace amplifier (AMP)  
Ignition controller (IC#)  
red LED blinks  
1 time, 2 times or 4 times  
Improper manifold pressure  
Set high and low manifold pressure  
No  
(refer to 4:1 Electronic Modulation Start-Up section)  
Faulty spark rod or spark gap does not equal 1/8 inch  
Everything is working properly,  
consult factory.  
Replace spark rod or adjust gap to 18 inch  
Model IG / IGX Make-Up Air  
53  
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Troubleshooting  
8:1 Staged Furnace Will Not Light  
No  
24 VAC across R and X?  
Main disconnect (DS1) open or defective  
Close, repair or replace  
Yes  
Main transformer (TR1) fault  
Replace main transformer  
No  
24 VAC across W1 and X?  
Yes  
Heat switch (S4) open or not wired  
Close or replace heat switch (S4)  
No  
24 VAC across 22 and 21?  
Yes  
Heat transformer (TR2) fault  
Replace heating transformer  
No  
Yes  
Yes  
Yes  
N.O. contact on heat relay (RH)  
closed?  
Yes  
Heat relay (RH) is not energized  
Check for loose connections. Repair of replace heat relay (RH)  
DT1 displayed on furnace  
controller (SC1)?  
No  
Discharge air sensor (TS2) not wired or defective  
Wire or replace discharge air sensor (TS2)  
OT1 displayed on furnace  
controller (SC1)?  
No  
Outdoor air sensor (TS1) not wired or defective  
Wire or replace outdoor temperature sensor (TS1)  
Blank screen on furnace  
controller (SC1)?  
No  
Furnace controller (SC1) defective or not powered  
Replace or wire furnace controller (SC1)  
No  
24 VAC across terminals  
S and T?  
Discharge temperature was above high limit control (HLC1)  
Wait for high limit to cool and reset  
Yes  
Inlet air sensor contact open  
Adjust inlet air sensor setting (refer to 8:1 Staged Start-Up section)  
Furnace controller (SC1) defective  
With the combustion blower  
(CM) off, is the N.O.  
airflow switch (PS2) closed?  
Yes  
Replace furnace controller (SC1)  
No  
Airflow switch (PS2) defective  
Replace defective airflow switch (PS2)  
Continues on next page...  
Model IG / IGX Make-Up Air  
54  
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Troubleshooting  
8:1 Staged Furnace Will Not Light  
... continued from  
previous page.  
With the combustion blower  
(CM) on for at least  
No  
30 seconds, is there  
24 VAC across T and A or E?  
Yes  
Furnace controller (SC1) defective  
Replace furnace controller (SC1)  
Ignition controller (IC#)  
Yes  
red LED  
blinks 7 times or is on  
No  
Ignition controller(s) (IC#) failed  
Replace faulty ignition controller(s)  
Ignition controller (IC#)  
Yes  
red LED blinks  
1 time, 2 times or 4 times  
Improper manifold pressure  
Set high and low manifold pressure  
(refer to 8:1 Staged Start-Up section)  
No  
Faulty spark rod or spark gap does not equal 1/8 inch  
Cycle power to the unit  
and wait 30 seconds  
Replace spark rod or adjust gap to 18 inch  
No  
Does the combustion relay  
(R9 or CR) close?  
Internal high limit tripped (temperature above set point)  
Let temperatures cool  
Internal inlet air sensor open  
Yes  
Adjust inlet air sensor setting (refer to 8:1 Staged Start-Up section)  
Combustion relay (R9 or CR) defective  
Replace defective combustion relay (R9 or CR)  
No  
Does the combustion  
blower (CM) run?  
Combustion blower fuse (FU9) blown  
Replace combustion blower fuse (FU9)  
Combustion blower (CM) defective  
Replace defective combustion blower (CM)  
Yes  
Does the combustion  
blower stop after  
Yes  
30 seconds of operation?  
Airflow switch (PS2) defective  
Replace defective airflow switch (PS2)  
Airflow relay (R9) defective  
No  
Replace defective airflow relay (R9)  
Everything is working properly,  
consult factory.  
Model IG / IGX Make-Up Air  
55  
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Troubleshooting  
Evaporative Cooler does not Operate (Recirculating pump)  
Supply fan must be on for cooler to operate  
No  
24 VAC between terminals  
Cool switch (S4) off  
Y1 and X  
(turn cool switch (S4) on)  
Cool switch not wired  
(wire cool switch (S4))  
Yes  
No  
No  
24 VAC between terminal A2 on  
Cooling Relay (RC) and X  
Optional inlet air sensor (TS4) holding  
(Adjust TS4 setting. Reference Blower Start-Up – Step #6)  
Yes  
115 VAC between terminals  
102 and 101  
Cooling transformer (TR4) defective  
(Replace transformer)  
Yes  
No  
115 VAC between terminal  
114 and 101  
Cooling relay (RC) is not energized  
(Check for loose connections)  
(Repair or replace relay)  
Yes  
At this time the evaporative cooler pumps should be on  
Water Blows through Evaporative Cooler  
Are the headers in place and  
No  
located near the entering  
air side of the media?  
Replace headers and/or move the headers  
Yes  
Yes  
Yes  
Water supply greater than  
evaporation and bleed-off rate?  
Use the main supply valve to reduce the supply of water  
No  
Air velocity greater than  
specified?  
Reduce the air velocity through the media  
(Reference Blower Start-Up – Step #5)  
No  
At this time the evaporative cooler should be  
operating without water blowing through  
Model IG / IGX Make-Up Air  
56  
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Troubleshooting  
Water Wizard™ — Improper Water Supply  
NOTE  
NOTE  
If the water supply is too low, the media will  
continuously appear dry.  
Changing the On Time Factor by (1) will change the  
water supply by approximately 3%.  
NOTE  
IMPORTANT  
If the water supply is too high, the media will be  
saturated and excessive water will be draining from  
the sump tank.  
The Enter key must be pressed to save the new On  
Time Factor.  
4. Exit Program Mode  
After 15 seconds of idle time the controller will  
automatically exit Program Mode.  
NOTE  
Some water drainage is desired to keep the media  
flushed, but it should be minimized to utilize the  
Water Wizard™.  
1. Adjust the Manual Supply Valve  
Adjust the manual supply valve (refer to Start-Up,  
Water Wizard™). If the recommended water pressure  
does not provide enough water, increase the pressure  
until the desired water supply is achieved. If the  
recommended water pressure provides too much  
water, decrease the water pressure until the desired  
water supply is achieved.  
CAUTION  
Only proceed to Steps 2 and 3 if Step 1 does not  
correct the problem.  
2. Enter Program Mode  
Press and hold  
the Enter key for  
three seconds to enter  
Program Mode. The  
display will read “Pro”  
when Program Mode is  
active.  
3. Adjust the On Time Factor  
While in the  
Program Menu,  
use the Up and  
Down keys to  
navigate through  
the menu options  
until “ont” is displayed.  
With “ont” displayed, press the Enter key to access  
the setting.  
With the setting displayed, use the Up and Down keys  
to adjust the setting as needed.  
Increase the factor to increase the water supply or  
decrease the factor to decrease the water supply.  
Press the Enter key to save the new On Time Factor  
and return to the Program Menu.  
Model IG / IGX Make-Up Air  
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Maintenance - Routine  
Wheels  
CAUTION  
Wheels require little attention when moving clean air.  
Occasionally oil and dust may accumulate on the  
wheel causing imbalance. When this occurs the wheel  
and housing should be cleaned to assure proper  
operation.  
Lock-out the gas and the electrical power to the  
unit before performing any maintenance or service  
operations to this unit.  
V-Belt Drives  
V-belt drives must be checked on a regular basis for  
wear, tension, alignment, and dirt accumulation.  
Bearings  
The bearings for our fans are carefully selected to  
match the maximum load and operating conditions  
of the specific class, arrangement and fan size.  
The instructions provided in this manual and those  
provided by the bearing manufacturer will minimize  
any bearing problems.  
Check the tension by measuring the deflection in the  
belt as shown below.  
Check the alignment by using a straight edge across  
both sheaves as shown below.  
IMPORTANT  
IMPORTANT  
Premature or frequent belt failures can be caused by  
improper belt tension, or misaligned sheaves.  
Lubricate bearings prior to periods of extended  
shutdowns or storage and rotate shaft monthly to  
aid in corrosion prevention. If the fan is stored more  
than three months, purge the bearings with new  
grease prior to start-up.  
• Abnormally high belt tension or drive misalignment  
will cause excessive bearing loads and may result  
in failure of the fan and/or motor bearings.  
• Abnormally low belt tension will cause squealing  
on start-up, excessive belt flutter, slippage, and  
overheated sheaves.  
Recommended Bearing Lubrication Schedule  
(in months*)  
IMPORTANT  
Bearing Bore Size (inches)  
Fan  
RPM  
Do not pry belts on or off the sheave. Loosen belt  
tension until belts can be removed by simply lifting  
the belts off the sheaves.  
1
2
-1  
118 -112  
158 -178 11516 -2316  
2716 -3  
250  
500  
6
6
6
5
3
3
2
1
6
6
4
2
2
1
1
6
5
6
4
6
6
5
5
5
5
IMPORTANT  
750  
3
3
When replacing V-belts on multiple groove drives,  
all belts should be changed to provide uniform drive  
loading.  
1000  
1250  
1500  
2000  
1
1
1
1
1
0.5  
0.25  
IMPORTANT  
0.5  
Do not install new belts on worn sheaves. If the  
sheaves have grooves worn in them, they must be  
replaced before new belts are installed.  
*Suggested initial greasing interval is based on 12 hour per  
day operation and 150°F maximum housing temperature.  
For continuous (24 hour) operation, decrease greasing  
interval by 50%  
Belt Span  
Deflection =  
• If extended grease lines are present, relubricate while in  
operation, only without endangering personnel.  
64  
• For ball bearings (operating) relubricate until clean grease  
is seen purging at the seals. Be sure not to unseat the seal  
by over lubricating.  
• For ball bearings (idle) add 1-2 shots of grease up to 2  
inch bore size, and 4-5 shots above 2 inch bore sizes with  
a hand grease gun.  
• For roller bearings add 4 shots of grease up to 2 inch bore  
size, and 8 shots for 2-5 inch bore size with a hand grease  
gun.  
Belt Span  
Belt Tension  
• Adjust relubrication frequency based on condition of  
purged grease.  
• A high quality lithium based grease conforming to NLGI  
Grade 2 consistency, such as those listed here:  
Drive Alignment  
Mobil 532  
Mobilux #2  
Texaco Multifak #2 B Shell Alavania #2  
Texaco Premium #2 Exxon Unirex #2  
Snow Accumulation  
Clear snow away from roof mounted units. Keep the  
snow clear of the intake and access doors.  
Model IG / IGX Make-Up Air  
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Motors  
Evaporative Coolers  
Motor maintenance is generally limited to cleaning  
and lubrication (where applicable).  
The media should be periodically brushed lightly with  
a soft bristle brush in an up and down motion while  
flushing with water. This aids in reducing the amount  
of mineral build-up.  
Cleaning should be limited to exterior surfaces only.  
Removing dust and grease build-up on the motor  
assures proper motor cooling.  
For large amounts of mineral build-up, clean or  
replace the media and increase the water bleed-off or  
flush rate.  
Motors supplied with grease fittings should be  
greased in accordance with the manufacturer’s  
recommendations.  
The cooling media has a useful life of 3 to 5 years  
depending on the water quality and the bleed-off or  
flush rate.  
IMPORTANT  
Do not allow water or solvents to enter the motor  
or bearings. Motors and bearings should never be  
sprayed with steam, water or solvents.  
IMPORTANT  
When reinstalling the evaporative media, make sure  
that it is installed correctly. Reference the drawing  
shown below.  
IMPORTANT  
Greasing motors is only intended when fittings are  
provided. Many motors are permanently lubricated,  
requiring no additional lubrication.  
IMPORTANT  
Replacement media should be from the same  
manufacturer and be the same size as the original  
media provided with the unit.  
Filters  
Filter maintenance is generally limited to cleaning and  
replacement.  
45º  
If aluminum mesh filters are installed, they can be  
washed in warm soapy water.  
An adhesive spray can be added to aluminum mesh  
filters to increase their efficiency.  
Entering Air  
Leaving Air  
If disposable filters are installed, they can be checked  
by holding up to a light source. If light cannot pass  
through the filter, it should be replaced.  
15º  
Media Orientation  
IMPORTANT  
When reinstalling filters, be sure to install them  
with the airflow in the correct direction. An airflow  
direction arrow is located on the side of the filters.  
Cooling Coils  
WARNING  
Repair and replacement of the coil and the  
connecting piping, valves, etc., should be performed  
by a qualified individual.  
IMPORTANT  
Replacement filters should be from the same  
manufacturer and the same size as the original  
filters provided with the unit.  
Inspect the coil for signs of corrosion and/or leaks.  
Repair any leaks as required.  
Chilled Water Coils  
Inspect the coil’s surface for foreign material. If the  
coil surface needs cleaning, clean the coil from the  
leaving air-side so that foreign material will be washed  
out of the coil rather than pushed farther in.  
Test the circulating fluid for sediment, corrosive  
products and biological contaminants. Make the  
necessary corrective measures.  
Maintain adequate fluid velocities and proper filtering  
of the fluid.  
Inspect and clean the drain pan to prevent the growth  
of algae and other organisms.  
If automatic air vents are not utilized, periodic venting  
of the coil is recommended to remove accumulated  
air.  
IMPORTANT  
Be sure to read and follow the manufacturer’s  
recommendations before using any cleaning fluid.  
CAUTION  
Caution should be used to avoid injury when venting  
the coil. High pressure and/or high temperature  
fluids can cause serious injuries.  
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Maintenance - Fall  
High Limit  
Heat Exchanger  
The high limit switch may have tripped over the  
summer; it should be checked and reset if necessary.  
The heat exchanger should be checked annually for  
cracks. If a crack is detected, the heat exchanger  
should be replaced before the unit is put back into  
operation. Also, airflow across the heat exchanger  
should be checked to make sure the blower is  
operating properly.  
CAUTION  
Lock-out the gas and the electrical power to the  
unit before performing any maintenance or service  
operations to this unit.  
Flue Collector Box  
The flue passageway and flue collector box should be  
inspected prior to each heating season and cleared of  
any debris.  
Gas Line  
Remove the drip leg and clean any liquid or debris  
that may have accumulated. Once the drip leg is  
cleaned, reattach it.  
Electrical Wiring  
The electrical wiring should be checked annually for  
loose connections or deterioration.  
Gas Train  
The gas connections, joints and valves should be  
checked annually for tightness. Apply a soap and  
water solution to all piping; watch for bubbling which  
indicates a leak. Other leak testing methods can be  
used.  
Replacement Parts  
When ordering replacement parts, include the  
complete unit model number and serial number listed  
on the unit nameplate.  
Evaporative Coolers  
The water should be shut off and all the lines drained  
when the outside temperature drops below 45ºF.  
Vent Piping  
Remove any debris from the drip legs on the  
combustion air and exhaust pipes.  
Remove drain plugs for the winter.  
Burners and Orifices  
Before each heating season, examine the burners and  
gas orifices to make sure they are clear of any debris  
such as spider webs, etc. Clean burner as follows:  
Clean all interior parts of any mineral deposits or  
foreign materials that may have built-up during the  
cooling season.  
Turn off both electrical and gas supplies to the unit.  
• Disconnect union between manifold and gas valve.  
• Remove manifold and burner assembly.  
• Inspect and clean orifices and burners as  
necessary. Avoid using any hard or sharp  
instruments which could cause damage to the  
orifices or burners.  
Replace any worn or non-functioning parts.  
Winterizing Chilled Water Coils  
During the winter, chilled water coils need to be  
protected against freezing. Manufacturer recommends  
protecting the coils by either blowing-out the coils or  
by flushing the coils.  
Blowing-Out Coils  
- Remove any soot deposits from the burner with  
a wire brush.  
- Clean the ports with an aerosol degreaser or  
compressed air.  
- Wipe the inside of the burner clean. Cleaning  
the burner with a degreaser will slow the future  
build-up of dirt.  
1. Close valves on the supply and return lines.  
2. Open drain valves and/or drain plug. Remove  
vent plug to allow coil to drain faster.  
3. After coil is fully drained, connect a blower to the  
caps. Do not connect the blower to the air vent  
or drain plug.  
4. Close the vent plug on the header that the blower  
is connected to. Open the drain valve or cap on  
the other header.  
5. Turn on blower for 30 minutes. Place mirror at  
discharge. If the mirror fogs up, repeat procedure  
until no fog appears on the mirror.  
• Before reinstalling the burner assembly, look down  
the heat exchanger tubes to make sure they are  
clear of any debris.  
• Reinstall manifold and burner assembly, reconnect  
wire leads and gas supply piping.  
6. After drying the coil, wait a few minutes then  
repeat Step #5.  
7. Leave drains open and do not install plugs until  
beginning of cooling season.  
Turn on the electrical power and gas supply.  
• Follow the start-up procedure to light the burners  
and verify proper operation.  
Model IG / IGX Make-Up Air  
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Flushing Coils  
Manufacturer recommends the use of inhibited glycol  
(such as propylene or ethylene) to flush water coils  
to protect against freezing. Additionally, the use of  
inhibited glycol provides corrosion protection.  
The table below indicates the percentage of glycol  
required to prevent freezing in a coil at a given outdoor  
air freeze point. Completely fill coil with solution. Drain  
coil. Residual glycol fluid per these concentrations  
can be left in the coil without concern of freezing.  
Recovered fluid can be used to flush other coils.  
Percent of  
Ethylene  
Glycol  
Percent of  
Propylene  
Glycol  
Freeze Point  
Freeze Point  
ºF  
ºC  
ºF  
ºC  
by Volume  
by Volume  
0
0
0
32  
25  
0
32  
26  
19  
8
-4  
-3  
10  
20  
30  
40  
50  
60  
10  
20  
30  
40  
50  
60  
-9  
-7  
16  
-16  
-25  
-37  
-48  
-13  
-22  
-33  
-51  
3
-13  
-34  
-55  
-7  
-28  
-60  
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Reference - Model IG Venting Connection Location  
Exhaust Outlet  
Venting Location Dimensions  
Combustion Air Inlet  
IG  
Housing  
A
B
C
D
E
G
10  
20  
30  
3.89  
3.91  
3.91  
5.12  
3.89  
3.89  
9.12  
7.89  
7.89  
11.59  
11.62  
11.62  
23.11  
25.34  
25.34  
27.58  
32.27  
32.27  
Discharge End  
Dimensions are in inches.  
Dimensions B and E are not needed for standard venting. A round  
adapter should be used for the exhaust connection.  
F
E
Flue Connection Size (diameter in inches)  
D
Standard  
Exhaust  
4.0  
Non-Concentric  
Concentric  
IG  
Housing  
Exhaust  
4.0  
Intake  
4.0  
Exhaust  
Intake  
6.0  
10  
20  
30  
4.0  
6.0  
6.0  
A
3/4-inch Gas Connection  
6.0  
6.0  
6.0  
8.0  
B
6.0  
6.0  
6.0  
8.0  
C
Reference - Model IGX Venting Connection Location  
Exhaust Air Outlet  
Combustion Air Intake  
Airflow  
D
C
A
B
Flue Connection Size (diameter in inches)  
Non-Concentric Concentric  
Exhaust Intake Exhaust  
4.0 4.0  
IGX  
Housing  
Furnace Size  
(MBH)  
A
B
C
D
Standard  
Exhaust  
4.0  
Intake  
6.0  
6.0  
8.0  
8.0  
6.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
8.0  
100  
150  
200  
250  
150  
200  
250  
300  
350  
400  
500  
600  
350  
400  
500  
600  
700  
800  
1050  
1200  
4.45  
4.45  
5.64  
5.64  
4.45  
5.67  
5.67  
5.67  
5.67  
5.67  
5.67  
5.67  
5.96  
5.96  
5.96  
5.96  
5.96  
5.96  
5.96  
5.96  
8.45  
8.45  
9.64  
9.64  
8.45  
9.67  
9.67  
9.67  
9.67  
9.67  
9.67  
9.67  
9.71  
9.71  
9.71  
9.71  
9.71  
9.71  
9.71  
9.71  
23.43  
23.43  
23.97  
23.97  
29.38  
24.97  
24.97  
24.97  
19.01  
19.01  
24.97  
24.97  
28.31  
28.31  
28.31  
28.31  
28.31  
28.31  
28.31  
28.31  
27.90  
27.90  
30.90  
30.90  
33.85  
31.90  
31.90  
31.90  
25.94  
25.94  
31.90  
31.90  
35.24  
35.24  
35.24  
35.24  
35.24  
35.24  
35.24  
35.24  
4.0  
4.0  
6.0  
6.0  
4.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
4.0  
6.0  
6.0  
4.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
4.0  
6.0  
6.0  
4.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
4.0  
6.0  
6.0  
4.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
6.0  
12  
22  
32  
6.0  
6.0  
6.0  
Dimensions are in inches. Dimensions A and C are not needed for standard venting.  
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16. Stage Controller - Provides single or two stage  
control of the furnace.  
17. Airflow Switch - Monitors the airflow inside the  
Reference - Model IG  
(Single or 2 Stage)  
heat exchanger.  
22  
24  
11  
18. Ignition Controller - Controls the ignition of the  
20  
17  
19  
10  
25  
furnace. Maintains safe operation of the furnace.  
19. Evaporative Cooling Fuses (Optional) - Provides  
proper fusing to evaporative cooling pump and  
controls.  
14  
13  
6
4
3
1
8
7
20. Transformer Fuse (Optional) - Provides proper  
16  
16  
15  
18  
fusing for evaporative cooling transformer.  
9
2
21. Cooling Relay (Optional) - Allows power to pass  
to cooling controls.  
22. Reset Timer (Optional) - Resets cooling system  
NOTE  
This is a typical blower control center, the control  
center in your unit may be different. Reference the  
ladder diagram on the inside of the control center  
door for a unit specific wiring diagram.  
to run a time interval.  
23. Auto Drain Relay (Optional) - Assures supply  
pump does not operate during drain interval.  
Allows pump to operate in cooling mode.  
24. Cooling Timer (Optional) - Allows for automatic  
draining of the evaporative cooling system based  
on time schedule.  
25. Dirty Filter Switch (Optional) - Monitors filter  
pressure drop. Turns on indicating light when  
pressure drop is above field adjustable set point.  
1. Supply Motor Starter - 24 volt magnetic contacts  
for starting supply motor.  
2. Supply Overload - Provides electronic overload  
protection to supply motor.  
3. Low Voltage Transformer - Provides low voltage  
to fan/heat/cooling enable controls, staged  
furnace controls and optional evaporative cooling  
controls.  
Staged Gas  
Valve  
Gas  
Pressure  
Test Port  
3/4 inch  
Gas Supply  
Connection  
Manifold  
4. Control Terminal Block - Provides wiring access  
to controls.  
5. Fan Relay - Allows power to pass to energize  
motor starter.  
6. Control Terminal Block - Provides wiring access  
to fan/heat/cooling enable controls.  
7. Auxiliary Contact (Optional) - Provides one  
normally closed and one normally open contact  
for other equipment.  
8. Exhaust Motor Starter (Optional) - 24 volt  
magnetic contacts for starting exhaust motor.  
9. Exhaust Overload (Optional) - Provides  
electronic overload protection to exhaust motor.  
10. Exhaust Fuses (Optional) - Provides proper  
fusing for exhaust fan motor(s).  
11. Building Freeze Protection Timer (Optional) -  
Prevents the discharge of cold air into the  
building.  
12. Heat Relay - Allows power to pass to heating  
controls.  
13. Low Voltage Transformer - Provides low voltage  
to the ignition controller.  
14. Heating Terminal Block - Provides wiring access  
to heating controls.  
15. Inlet Air Sensor (Optional) - Outdoor air stat that  
automatically controls the heating and/or cooling  
based on outdoor air temperature.  
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16. Stage Controller - Provides 8 stage control of the  
Reference - Model IG  
(8:1 Staged)  
furnace.  
17. Airflow Switch - Monitors the airflow inside the  
heat exchanger.  
24  
11  
22  
17  
18. Ignition Controller - Controls the ignition of the  
20  
19  
25  
10  
furnace. Maintains safe operation of the furnace.  
16  
19. Evaporative Cooling Fuses (Optional) - Provides  
proper fusing to evaporative cooling pump and  
controls.  
14  
13  
6
4
1
8
7
20. Transformer Fuse (Optional) - Provides proper  
18  
15  
18  
3
fusing for evaporative cooling transformer.  
9
2
21. Cooling Relay (Optional) - Allows power to pass  
to cooling controls.  
22. Reset Timer (Optional) - Resets cooling system  
NOTE  
This is a typical blower control center, the control  
center in your unit may be different. Reference the  
ladder diagram on the inside of the control center  
door for a unit specific wiring diagram.  
to run a time interval.  
23. Auto Drain Relay (Optional) - Assures supply  
pump does not operate during drain interval.  
Allows pump to operate in cooling mode.  
24. Cooling Timer (Optional) - Allows for automatic  
draining of the evaporative cooling system based  
on time schedule.  
1. Supply Motor Starter - 24 volt magnetic contacts  
for starting supply motor.  
25. Dirty Filter Switch (Optional) - Monitors filter  
pressure drop. Turns on indicating light when  
pressure drop is above field adjustable set point.  
2. Supply Overload - Provides electronic overload  
protection to supply motor.  
3. Low Voltage Transformer - Provides low voltage  
to fan/heat/cooling enable controls, staged  
furnace controls and optional evaporative cooling  
controls.  
3/4 inch  
Gas Supply  
Connection  
Staged Gas  
Valves  
Gas  
Pressure  
Test Port  
4. Control Terminal Block - Provides wiring access  
Gas Pressure  
Test Port  
to controls.  
Small  
Manifold  
Large  
Manifold  
5. Fan Relay - Allows power to pass to energize  
motor starter.  
6. Control Terminal Block - Provides wiring access  
to fan/heat/cooling enable controls.  
7. Auxiliary Contact (Optional) - Provides one  
normally closed and one normally open contact  
for other equipment.  
8. Exhaust Motor Starter (Optional) - 24 volt  
magnetic contacts for starting exhaust motor.  
9. Exhaust Overload (Optional) - Provides  
electronic overload protection to exhaust motor.  
10. Exhaust Fuses (Optional) - Provides proper  
fusing for exhaust fan motor(s).  
11. Building Freeze Protection Timer (Optional) -  
Prevents the discharge of cold air into the  
building.  
12. Heat Relay - Allows power to pass to heating  
controls.  
13. Low Voltage Transformer - Provides low voltage  
to the ignition controller.  
14. Heating Terminal Block - Provides wiring access  
to heating controls.  
15. Inlet Air Sensor (Optional) - Outdoor air stat that  
automatically controls the heating and/or cooling  
based on outdoor air temperature.  
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16. Amplifier - Controls the modulating valve based  
on the input from the temperature selector and the  
discharge air sensor.  
Reference - Model IG  
(2:1 Modulation)  
17. Airflow Switch - Monitors the airflow inside the  
11  
18  
17  
heat exchanger.  
21  
20  
26  
10  
18. Temperature Selector - Allows the user to adjust  
23  
25  
discharge air temperature.  
14  
19. Ignition Controller - Controls the ignition of the  
13  
6
4
3
furnace. Maintains safe operation of the furnace.  
1
8
7
20. Evaporative Cooling Fuses (Optional) - Provides  
proper fusing to evaporative cooling pump and  
controls.  
15  
19  
16  
9
2
21. Transformer Fuse (Optional) - Provides proper  
fusing for evaporative cooling transformer.  
22. Cooling Relay (Optional) - Allows power to pass  
NOTE  
This is a typical blower control center, the control  
center in your unit may be different. Reference the  
ladder diagram on the inside of the control center  
door for a unit specific wiring diagram.  
to cooling controls.  
23. Reset Timer (Optional) - Resets cooling system  
to run a time interval.  
24. Auto Drain Relay (Optional) - Assures supply  
pump does not operate during drain interval.  
Allows pump to operate in cooling mode.  
1. Supply Motor Starter - 24 volt magnetic contacts  
for starting supply motor.  
25. Cooling Timer (Optional) - Allows for automatic  
draining of the evaporative cooling system based  
on time schedule.  
26. Dirty Filter Switch (Optional) - Monitors filter  
pressure drop. Turns on indicating light when  
pressure drop is above field adjustable set point.  
2. Supply Overload - Provides electronic overload  
protection to supply motor.  
3. Low Voltage Transformer - Provides low voltage  
to fan/heat/cooling enable controls, modulating  
furnace controls and optional evaporative cooling  
controls.  
4. Control Terminal Block - Provides wiring access  
Gas Pressure  
Test Port  
to controls.  
3/4 inch  
Gas Supply  
Connection  
5. Fan Relay - Allows power to pass to energize  
Manifold  
motor starter.  
6. Control Terminal Block - Provides wiring access  
Staged  
Gas Valve  
to fan/heat/cooling enable controls.  
7. Auxiliary Contact (Optional) - Provides one  
normally closed and one normally open contact  
for other equipment.  
Modulating  
Gas Valve  
8. Exhaust Motor Starter (Optional) - 24 volt  
magnetic contacts for starting exhaust motor.  
9. Exhaust Overload (Optional) - Provides  
electronic overload protection to exhaust motor.  
10. Exhaust Fuses (Optional) - Provides proper  
fusing for exhaust fan motor(s).  
11. Building Freeze Protection Timer (Optional) -  
Prevents the discharge of cold air into the  
building.  
12. Heat Relay - Allows power to pass to heating  
controls.  
13. Low Voltage Transformer - Provides low voltage  
to the ignition controller.  
14. Heating Terminal Block - Provides wiring access  
to heating controls.  
15. Inlet Air Sensor (Optional) - Outdoor air stat that  
automatically controls the heating and/or cooling  
based on outdoor air temperature.  
Model IG / IGX Make-Up Air  
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16. Modulation Controller - Provides 4:1 modulating  
Reference - Model IG  
(4:1 Modulation)  
turndown control of the furnace.  
17. Amplifier - Controls the modulating valve based  
on the input from the modulation controller  
settings and the discharge air sensor.  
25  
11  
23  
18  
20 21  
10  
26  
18  
18. Airflow Switch - Monitors the airflow inside the  
16  
heat exchanger.  
14  
19. Ignition Controller - Controls the ignition of the  
13  
6
4
furnace. Maintains safe operation of the furnace.  
1
8
7
20. Modulation Controller (Optional) - Provides  
15  
19  
17  
3
proper fusing to modulation controller.  
9
2
21. Transformer Fuse (Optional) - Provides proper  
fusing to low voltage transformer.  
22. Cooling Relay (Optional) - Allows power to pass  
to cooling controls.  
23. Reset Timer (Optional) - Resets cooling system  
NOTE  
This is a typical blower control center, the control  
center in your unit may be different. Reference the  
ladder diagram on the inside of the control center  
door for a unit specific wiring diagram.  
to run a time interval.  
24. Auto Drain Relay (Optional) - Assures supply  
pump does not operate during drain interval.  
Allows pump to operate in cooling mode.  
1. Supply Motor Starter - 24 volt magnetic contacts  
for starting supply motor.  
2. Supply Overload - Provides electronic overload  
25. Cooling Timer (Optional) - Allows for automatic  
draining of the evaporative cooling system based  
on time schedule.  
protection to supply motor.  
26. Dirty Filter Switch (Optional) - Monitors filter  
pressure drop. Turns on indicating light when  
pressure drop is above field adjustable set point.  
3. Low Voltage Transformer - Provides low voltage  
to fan/heat/cooling enable controls, modulating  
furnace controls and optional evaporative cooling  
controls.  
Modulating  
Gas Valve  
Gas Pressure  
4. Control Terminal Block - Provides wiring access  
Test Port  
to controls.  
3/4 inch  
Gas Supply  
Connection  
Manifold  
5. Fan Relay - Allows power to pass to energize  
motor starter.  
Staged  
Gas Valve  
6. Control Terminal Block - Provides wiring access  
to fan/heat/cooling enable controls.  
7. Auxiliary Contact (Optional) - Provides one  
normally closed and one normally open contact  
for other equipment.  
8. Exhaust Motor Starter (Optional) - 24 volt  
magnetic contacts for starting exhaust motor.  
9. Exhaust Overload (Optional) - Provides  
electronic overload protection to exhaust motor.  
10. Exhaust Fuses (Optional) - Provides proper  
fusing for exhaust fan motor(s).  
11. Building Freeze Protection Timer (Optional) -  
Prevents the discharge of cold air into the  
building.  
12. Heat Relay - Allows power to pass to heating  
controls.  
13. Low Voltage Transformer - Provides low voltage  
to the ignition controller.  
14. Heating Terminal Block - Provides wiring access  
to heating controls.  
15. Inlet Air Sensor (Optional) - Outdoor air stat that  
automatically controls the heating and/or cooling  
based on outdoor air temperature.  
Model IG / IGX Make-Up Air  
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16. Cooling Relay (Optional) - Allows power to pass  
to cooling controls.  
17. Reset Timer (Optional) - Resets cooling system  
Reference - Model IGX  
(Blower Control Center)  
to run a time interval.  
18. Auto Drain Relay (Optional) - Assures supply  
pump does not operate during drain interval.  
Allows pump to operate in cooling mode.  
14  
15  
9
3
12  
19. Cooling Timer (Optional) - Allows for automatic  
draining of the evaporative cooling system based  
on time schedule.  
10  
4
7
1
6
20. Dirty Filter Switch (Optional) - Monitors filter  
pressure drop. Turns on indicating light when  
pressure drop is above field adjustable set point.  
17  
19  
8
2
13  
20  
NOTE  
This is a typical blower control center, the control  
center in your unit may be different. Reference the  
ladder diagram on the inside of the control center  
door for a unit specific wiring diagram.  
1. Supply Motor Starter - 24 volt magnetic contacts  
for starting supply motor.  
2. Supply Overload - Provides electronic overload  
protection to supply motor.  
3. Low Voltage Transformer - Provides low voltage  
to fan/heat/cooling enable controls.  
4. Control Terminal Block - Provides wiring access  
to controls.  
5. Fan Relay - Allows power to pass to energize  
motor starter.  
6. Auxiliary Contact (Optional) - Provides one  
normally closed and one normally open contact  
for other equipment.  
7. Exhaust Motor Starter (Optional) - 24 volt  
magnetic contacts for starting exhaust motor.  
8. Exhaust Overload (Optional) - Provides  
electronic overload protection to exhaust motor.  
9. Exhaust Fuses (Optional) - Provides proper  
fusing for exhaust fan motor(s).  
10. Building Freeze Protection Timer (Optional) -  
Prevents the discharge of cold air into the  
building.  
11. Heat Relay - Allows power to pass to heating  
controls.  
12. Low Voltage Transformer - Provides low voltage  
to the optional evaporative cooling controls.  
13. Inlet Air Sensor (Optional) - Outdoor air stat that  
automatically controls the heating and/or cooling  
based on outdoor air temperature.  
14. Evaporative Cooling Fuses (Optional) - Provides  
proper fusing to evaporative cooling pump and  
controls.  
15. Transformer Fuse (Optional) - Provides proper  
fusing for evaporative cooling transformer.  
Model IG / IGX Make-Up Air  
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Reference - Model IGX  
(Single or 2 Stage)  
Reference - Model IGX  
(8:1 Staged)  
Manifold  
Small Manifold  
9
8
5
5
5
2
7
Gas Pressure  
Test Port  
Gas Pressure  
Test Port  
1
1
2
Large Manifold  
7
3
6
3
Staged  
Gas Valve  
4
4
Gas Pressure  
Test Port  
3/4 inch  
Gas Supply  
Connection  
6
10  
Staged  
Gas Valve  
7
9
11  
8
3/4 inch Gas Supply  
Connection  
NOTE  
NOTE  
This is a typical furnace control center, the control  
center in your unit may be different. Reference the  
ladder diagram on the inside of the control center  
door for a unit specific wiring diagram.  
This is a typical furnace control center, the control  
center in your unit may be different. Reference the  
ladder diagram on the inside of the control center  
door for a unit specific wiring diagram.  
1. Low Voltage Transformer - Provides low voltage  
1. Low Voltage Transformer - Provides low voltage  
to the ignition controller.  
to the staged controller.  
2. Low Voltage Transformer - Provides low voltage  
2. Low Voltage Transformer - Provides low voltage  
to the ignition stage controller.  
to the ignition controllers.  
3. Control Terminal Block - Provides wiring access  
3. Control Terminal Block - Provides wiring access  
to heat controls.  
to controls.  
4. Control Terminal Block - Provides wiring access  
4. Control Terminal Block - Provides wiring access  
to heat/combustion blower controls.  
to controls.  
5. Stage Controller - Provides single or two  
stages of furnace control based on discharge air  
temperature set point.  
5. Input Converter - Receives and converts signal  
from Building Management Systems (BMS).  
6. Stage Controller - Provides eight stages of  
6. Ignition Controller - Controls the ignition of the  
control based on discharge temperature set point.  
furnace. Maintains safe operation of the furnace.  
7. Ignition Controllers - Controls the ignition of the  
7. Combustion Blower Contact - Passes power to  
furnace. Maintains safe operation of the furnace.  
the combustion blower.  
8. Contactor Relay - Allows power to pass to the  
8. Airflow Switch - Monitors the airflow inside the  
heat exchanger to ensure proper combustion  
airflow.  
combustion blower contact.  
9. Air Proving Switch Relay - Functions as a relay  
for the pressure switch.  
9. High Fire Relay - Allows furnace to ignite on high  
10. Combustion Blower Contact - Passes power to  
fire.  
the combustion blower.  
11. Airflow Switch - Monitors the airflow inside the  
heat exchanger.  
Model IG / IGX Make-Up Air  
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Reference - Model IGX  
(2:1 Modulation)  
Reference - Model IGX  
(4:1 Modulation)  
Manifold  
Manifold  
6
5
10  
9
3
1
Gas Pressure  
Test Port  
Gas Pressure  
Test Port  
6
4
1
2
7
4
2
5
3
Modulating  
Gas Valve  
Staged  
Gas Valve  
Modulating  
Gas Valve  
Staged  
Gas Valve  
8
11  
11  
7
9
8
3/4 inch Gas Supply  
Connection  
3/4 inch Gas Supply  
Connection  
NOTE  
NOTE  
This is a typical furnace control center, the control  
center in your unit may be different. Reference the  
ladder diagram on the inside of the control center  
door for a unit specific wiring diagram.  
This is a typical furnace control center, the control  
center in your unit may be different. Reference the  
ladder diagram on the inside of the control center  
door for a unit specific wiring diagram.  
1. Low Voltage Transformer - Provides low voltage  
1. Low Voltage Transformer - Provides low voltage  
to the ignition controller and amplifier.  
to the ignition controller.  
2. Control Terminal Block - Provides wiring access  
2. Low Voltage Transformer - Provides low voltage  
to heat controls.  
to the 4:1 electronic modulation controller.  
3. Control Terminal Block - Provides wiring access  
3. Low Voltage Transformer - Provides low voltage  
to heat controls.  
to the amplifier.  
4. Ignition Controller - Controls the ignition of the  
4. Control Terminal Block - Provides wiring access  
furnace. Maintains safe operation of the furnace.  
to controls.  
5. Amplifier - Controls the modulating valve based  
on the input from the temperature selector and the  
discharge air sensor.  
5. Control Terminal Block - Provides wiring access  
to controls.  
6. Input Converter - Receives and converts signal  
6. Temperature Selector - Allows the user to adjust  
from Building Management System (BMS).  
discharge air temperature.  
7. Ignition Controllers - Controls the ignition of the  
7. Combustion Blower Contact - Passes power to  
furnace. Maintains safe operation of the furnace.  
the combustion blower.  
8. Modulation Controller - Provides 4:1 modulation  
turndown control of furnace based on the  
discharge air temperature.  
9. Amplifier - Controls the modulating valve based  
on the input from the modulation controller  
settings and discharge air temperature sensor  
reading.  
8. Airflow Switch - Monitors the airflow inside the  
heat exchanger to ensure proper combustion  
airflow.  
9. High Fire Relay - Allows furnace to ignite on high  
fire.  
10. Combustion Blower Relay - Passes power to the  
variable speed combustion blower.  
11. Airflow Switches - Monitors the airflow inside  
the heat exchanger to ensure proper combustion  
airflow.  
Model IG / IGX Make-Up Air  
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Reference - Performance Table  
Performance Table  
The following table gives the air volume in cubic feet per minute that is required to provide the desired  
temperature rise for a given heating input. Model IG has a maximum 7,000 CFM capacity.  
Temperature Rise (ºF)  
55 60 65 70  
2963 2469 2116 1852 1646 1481 1347 1235 1140 1058  
Input Output  
(MBH) (MBH)  
25  
30  
35  
40  
45  
50  
75  
80  
85  
90  
95  
100  
741  
100  
150  
200  
250  
300  
350  
400  
500  
600  
700  
800  
1050  
1200  
80  
988  
926  
871  
823  
780  
120  
160  
200  
240  
4444 3704 3175 2778 2469 2222 2020 1852 1709 1587 1481 1389 1307 1235 1170 1111  
5926 4938 4233 3704 3292 2963 2694 2469 2279 2116 1975 1852 1743 1646 1559 1481  
7407 6173 5291 4630 4115 3704 3367 3086 2849 2646 2469 2315 2179 2058 1949 1852  
8889 7407 6349 5556 4938 4444 4040 3704 3419 3175 2963 2778 2614 2469 2339 2222  
280 10370 8642 7407 6481 5761 5185 4714 4321 3989 3704 3457 3241 3050 2881 2729 2593  
320 11852 9877 8466 7407 6584 5926 5387 4938 4558 4233 3951 3704 3486 3292 3119 2963  
400 14815 12346 10582 9259 8230 7407 6734 6173 5698 5291 4938 4630 4357 4115 3899 3704  
480  
560  
640  
840  
960  
NA  
NA  
NA  
NA  
NA  
14815 12698 11111 9877 8889 8081 7407 6838 6349 5926 5556 5229 4938 4678 4444  
NA  
NA  
NA  
NA  
14815 12963 11523 10370 9428 8642 7977 7407 6914 6481 6100 5761 5458 5185  
NA  
NA  
NA  
14815 13169 11852 10774 9877 9117 8466 7901 7407 6972 6584 6238 5926  
NA  
NA  
NA  
NA  
NA  
NA  
14141 12963 11966 11111 10370 9722 9150 8642 8187 7778  
NA 14815 13675 12698 11852 11111 10458 9877 9357 8889  
Model IG / IGX Make-Up Air  
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Reference - Start-Up Checklist  
Start-Up Checklist  
Unit Model Number ____________________________ (e.g. IGX-120-H32-DB)  
Unit Serial Number ____________________________ (e.g. 10111000)  
Start-Up Date ____________________________  
Start-Up Personnel Name ____________________________  
Start-Up Company ____________________________  
Phone Number ____________________________  
Pre Start-Up Checklist - check boxes as items are completed  
o
o
o
o
o
o
Check tightness of all factory wiring connections  
Verify control wiring wire gauge  
Hand-rotate blower to verify free rotation  
Verify supply voltage to the main disconnect  
Verify the supply gas pressure  
Verify remote controls wiring  
Start-Up Blower Checklist - refer to Blower Start-Up section for further detail  
o
o
o
o
o
o
o
Check line voltage  
Check blower rotation  
Check for vibration  
Supply fan RPM  
Motor nameplate amps  
Actual motor amps  
Actual CFM delivered  
L1-L2 _________________ L2-L3 _______________  
L1-L3 _______________  
_____________ RPM  
_____________ Amps  
_____________ Amps  
_____________ CFM  
Optional Accessories - refer to Blower Start-Up section, Step #6 for further detail  
o
o
o
o
Heating inlet air sensor  
Cooling inlet air sensor  
Building freeze protection  
Dirty filter gauge  
_____________ Actual Setting (Typical Setting 60-70ºF)  
_____________ Actual Setting (Typical Setting 75ºF)  
_____________ Actual Setting (Typical Setting 5 min; 45ºF)  
_____________ Actual Setting (Typical Setting varies)  
Start-Up Indirect Gas - refer to Furnace Start-Up section for further detail  
Furnace 1  
o
o
o
o
o
Determine furnace control type  
Check supply gas pressure _____________ Maximum  
Set the High Manifold pressure  
Set the Low Manifold pressure  
Set the unit’s operating temperature  
1 Stage - 2 Stage - 8 Stage - 2:1 Mod. - 4:1 Mod.  
__________ Minimum __________ Actual  
_____________ in. wg  
_____________ in. wg  
_____________ degrees F  
Furnace 2 (Optional)  
o
o
o
o
Determine furnace control type  
Check supply gas pressure ____________ Maximum  
Set the High Manifold pressure  
Set the Low Manifold pressure  
1 Stage - 2 Stage - 8 Stage - 2:1 Mod. - 4:1 Mod.  
__________ Minimum __________ Actual  
_____________ in. wg  
_____________ in. wg  
Furnace 3 (Optional)  
o
o
o
o
Determine furnace control type  
Check supply gas pressure ____________ Maximum  
Set the High Manifold pressure  
Set the Low Manifold pressure  
1 Stage - 2 Stage - 8 Stage - 2:1 Mod. - 4:1 Mod.  
__________ Minimum  
_____________ in. wg  
_____________ in. wg  
__________ Actual  
Model IG / IGX Make-Up Air  
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Maintenance Log  
Date __________________ Time _____________ AM/PM  
Notes:___________________________________________  
_________________________________________________  
_________________________________________________  
_________________________________________________  
_________________________________________________  
Date __________________ Time _____________ AM/PM  
Notes:___________________________________________  
_________________________________________________  
_________________________________________________  
_________________________________________________  
_________________________________________________  
Date __________________ Time _____________ AM/PM  
Notes:___________________________________________  
_________________________________________________  
_________________________________________________  
_________________________________________________  
_________________________________________________  
Date __________________ Time _____________ AM/PM  
Notes:___________________________________________  
_________________________________________________  
_________________________________________________  
_________________________________________________  
_________________________________________________  
Date __________________ Time _____________ AM/PM  
Notes:___________________________________________  
_________________________________________________  
_________________________________________________  
_________________________________________________  
_________________________________________________  
Date __________________ Time _____________ AM/PM  
Notes:___________________________________________  
_________________________________________________  
_________________________________________________  
_________________________________________________  
_________________________________________________  
Warranty  
Greenheck warrants this equipment to be free from defects in material and workmanship for a period of one year from  
the shipment date. Any units or parts which prove defective during the warranty period will be replaced at our option  
when returned to our factory, transportation prepaid. Motors are warranted by the motor manufacturer for a period of  
one year. Should motors furnished by Greenheck prove defective during this period, they should be returned to the  
nearest authorized motor service station. Greenheck will not be responsible for any removal or installation costs.  
As a result of our commitment to continuous improvement, Greenheck reserves the right to change specifications  
without notice.  
Greenheck Catalogs IG, IGX, IG-HV and IGX-HV provide  
additional information describing the equipment, fan  
performance, available accessories, and specification data.  
AMCA Publication 410-96, Safety Practices for Users and  
Installers of Industrial and Commercial Fans, provides  
additional safety information. This publication can be  
®
470656 • IG / IGX Make-Up Air, Rev. 5, May 2012  
Copyright 2012 © Greenheck Fan Corporation  
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