48A2,A3,A4,A5020-060
Single-Package Rooftop
Gas Heating/Electric Cooling Units
with COMFORTLINK™ Controls and Scroll Compressors
User’s Information Manual
NOTE TO INSTALLER
TO LIGHT UNIT
This manual should be left with the equipment owner.
DANGER
1. Do not turn off the electrical power to unit without
first turning off the gas supply.
2. Before attempting to start the gas heating section,
familiarize yourself with all the procedures that must
be followed.
WARNING: If the information in this
manual is not followed exactly, a fire or
explosion may result causing property
damage, personal injury or loss of life.
— Do not store or use gasoline or other
flammable vapors and liquids in the
vicinity of this or any other appliance.
— WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
3. Never attempt to manually light the burners on the
unit with a match, lighter, or any other flame. If the
electric sparking device fails to light the burners, refer
to the shutdown procedures, then call your dealer as
soon as possible.
If you do not follow these instructions exactly, a fire or
explosion may result, causing property damage, injury, or
loss of life.
• Do not touch any electrical switch;
do not use any phone in your
building.
• Immediately call your gas supplier
from a neighbor’s phone. Follow the
gas supplier’s instructions.
• If you cannot reach your gas sup-
plier, call the fire department.
See Fig. 1 and 2 for location of gas valve. Refer to Fig. 3
while performing the following steps.
1. Disable unit operation by using the scrolling marquee.
The scrolling marquee is located in the control box at the
compressor end of the unit.
— Installation and service must be per-
formed by a qualified installer, service
agency or the gas supplier.
ESCAPE
a. Push the
is shown.
key unit a blank display screen
b. Push the
lit.
key until the SERVICE TEST LED is
c. Push the ENTER key. The display will show
STOP.
WARNING
NOTE: Items in the Configuration and Service
Test modes are password protected. The display
will flash PASS and WORD when required. Use
the ENTER and arrow keys to enter the 4 digits of
the password. The default password is 1111.
Improper installation, adjustment, alteration, ser-
vice or maintenance can cause injury or property
damage. Refer to this manual. For assistance or
additional information consult a qualified installer,
service agency, or the gas supplier.
ENTER
or
d. Push the
key again. The NO/YES display
key to toggle the display to
will flash.
e. Push the
ENTER
YES and then push
. The unit will be
WARNING
locked off from heating, cooling or any operation.
The controls will still function and the display will
still operate.
Before performing recommended maintenance, be sure
main power switch to unit is turned off and lockout tag is
installed. Electrical shock could cause personal injury.
2. Close the field-installed manual gas shutoff valve.
3. Turn off the electrical power to the unit using the optional
disconnect or the field-installed disconnect and lock off
using proper lockout and tag-out procedures.
Your combination heating/cooling unit is equipped with
direct spark ignition and induced draft power combustion
blower.
4. Remove the gas section panels.
5. Move the switch on the gas valve to the OFF position and
wait 5 minutes.
WARNING
NOTE: If this is the first installation of the unit, the gas
flue hoods must be installed before operating unit. These
must be installed for the unit to run properly.
Burners will light automatically. Do not attempt to light by
hand; personal injury may result.
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Catalog No. 04-53480052-01 Printed in U.S.A. Form 48A-5SO Pg 1 3-08 Replaces: 48A-3SO
Book 1
Tab 1a
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a48-925tf
MODE
Run Status
Service Test
Temperature
a30-2239ef
Pressures
Setpoints
Inputs
Alarm Status
Outputs
Configuration
Time Clock
Operating Modes
Alarms
ESCAPE ENTER
a48-924tf
STEP 1
STEP 2
STEP 3
a48-3767tf
STEP 4
STEP 5
a48-3768tf
STEP 6
STEP 7
MODE
Run Status
Service Test
Temperature
a30-2239ef
Pressures
Setpoints
Inputs
Alarm Status
Outputs
Configuration
Time Clock
Operating Modes
Alarms
ESCAPE ENTER
a48-931tf
a48-930tf
STEP 8
STEP 9
STEP 10
Fig. 3 — To Light Unit
3
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6. Move the switch on the gas valve to the ON position.
7. Replace the gas section access panels.
ENTER
and arrow keys to enter the 4 digits of the
password. The default password is 1111.
8. Turn on the electrical supply to the units.
9. Open the field-installed manual gas valve.
10. Using the scrolling marquee, enable the unit to run using
the following procedure:
ENTER
or
d. Push the
key again. The NO/YES display
key to toggle the display to
will flash.
e. Push the
YES and then push ENTER . The unit will be
locked off from heating, cooling or any operation.
The controls will still function and the display will
still operate.
a. Push the ESCAPE key unit a blank display screen
is shown.
b. Push the
lit.
key until the SERVICE TEST LED is
2. Close the field-installed manual gas shutoff valve.
3. Turn off the electrical power to the unit using the optional
disconnect or the field-installed disconnect and lock off
using proper lockout and tag-out procedures.
ENTER
c. Push the
STOP.
key. The display will show
d. Push the ENTER key again. The NO/YES display
will flash.
4. Remove the gas section panels.
5. Move the switch on the gas valve to the OFF position and
wait 5 minutes before doing any service in the section or
on the piping.
e. Push the
or
key to toggle the display to
ENTER
NO and then push
normal operation and exit Service Test mode.
. The unit will return to
6. Replace gas section access panels.
7. If unit is being shut down because of a malfunction, call
11. To test the operation of the gas section, use the scrolling
marquee Service Test routine to energize the gas outputs
and to turn on the gas. Refer to unit Controls, Start-Up,
Operation, Service and Troubleshooting literature for
more information.
12. For normal operation, make sure that units with a conven-
tional thermostat are set to heating control temperature.
On VAV (variable air volume) and CV (constant volume)
units with a space temperature sensor, make sure that the
set points are at the normal heat set points.
your dealer as soon as possible.
If unit is being shut down because the heating season has
ended, restore electrical power to the unit and reset the
scrolling marquee to Run mode to ensure operation of the
cooling system during the cooling season.
IMPORTANT: Should overheating occur or the gas supply
fail to shut off, shut off the manual gas valve to the unit
before shutting off the electrical supply.
Do not use this unit if any part has been under water. Imme-
diately call a qualified service technician to inspect the unit and
to replace any part of the control system and gas control that
has been under water.
WARNING
If the main burners fail to light or the blower fails to start,
shut down gas heating section and call your dealer for ser-
vice. Failure to follow these requirements could result in
serious personal injury.
MAINTAINING YOUR UNIT
All maintenance should be handled by skilled, experienced
personnel. Your dealer can help you establish a standard
procedure.
For your safety, keep the area around the unit clear and free
of combustible materials, gasoline, and other flammable
liquids and vapors.
TO SHUT UNIT OFF
WARNING
To ensure proper functioning of the unit, the flow of com-
bustion and ventilating air must not be obstructed from reach-
ing the unit. Clearance of at least 4 ft on flue and condenser
sides and 6 in. on all other sides is required.
1. Do not turn off the electrical power to unit without
first turning off the gas supply.
2. Never attempt to manually light the main burners on
unit with a match, lighter, or any other flame. If the
electric sparking device fails to light the main burners,
refer to the following shutdown procedures. Call your
dealer as soon as possible.
ROUTINE MAINTENANCE AND CARE
FOR THE EQUIPMENT OWNER
Failure to follow these procedures can result in serious
fire or personal injury.
Consider the following information before maintaining or
servicing equipment:
Refer to Fig. 4 while performing the following steps:
WARNING
1. Disable unit operation by using the scrolling marquee.
The scrolling marquee is located in the control box at the
compressor end of the unit.
1. TURN OFF GAS SUPPLY AND THEN ELECTRI-
CAL POWER TO YOUR UNIT BEFORE SERVIC-
ING OR PERFORMING MAINTENANCE.
2. Do not turn off electrical power to this unit without
first turning off the gas supply.
a. Push the ESCAPE key unit a blank display screen
is shown.
3. When removing access panels or performing mainte-
nance functions inside your unit, be aware of sharp
sheet metal parts and screws. Although special care
has been taken to reduce sharp edges inside the unit,
be extremely careful when handling parts or reaching
into the unit.
b. Push the
lit.
key until the SERVICE TEST LED is
ENTER
c. Push the
STOP.
key. The display will show
NOTE: Items in the configuration and Service Test
modes are password protected. The display will
flash PASS and WORD when required. Use the
Failure to follow these procedures can result in serious
fire or personal injury.
4
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a48-925tf
MODE
Run Status
Service Test
Temperature
a30-2239ef
Pressures
Setpoints
Inputs
Alarm Status
Outputs
Configuration
Time Clock
Operating Modes
Alarms
ESCAPE ENTER
a48-924tf
STEP 1
STEP 2
STEP 3
a48-3767tf
STEP 4
a48-3768tf
STEP 5
STEP 6
Fig. 4 — To Shut Unit Off
5
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Air Filter(s) — Air filter(s) should be checked monthly
and changed when necessary. Units may have either 2-in. or
4-in. thick filters. For units with 2-in. thick filters, all filters will
be 20 x 24 x 2-in. size. For units with 4-in. thick filters, half the
filters will be 20 x 24 x 4-in. size and half will be 20 x 20 x
4-in. size. The filter access panel is located at the end of the unit
opposite of the condenser section. The access door is labeled to
indicate that it is the filter access door.
To replace or inspect filters:
1. Loosen the 3 latches securing the filter access door and
open door.
Indoor-Fan Motor, Outdoor-Fan Motor, and
Combustion Fan Motor — Lubrication is not recom-
mended. Bearings will not require lubrication for at least
5 years of normal operation. After 5 years, motor life can be
extended by having the motors serviced at an authorized motor
service shop.
Fan Shaft Bearings — The bearings should be greased
with Shell Alvania no. 2 grease or equivalent. The bearings
will need to be greased annually, dependent on fan usage. Do
not grease more than once a year.
Evaporator and Condenser Coils — Cleaning of
the coils should be done by qualified service personnel.
Contact your dealer for the required annual maintenance.
2. Remove the bolt securing the inner access panel, located
behind the filter access door, using care not to lose the
bolt.
3. Remove the inner access panel.
Condensate Drain — The drain pan and condensate
drain line should be checked and cleaned at the same time the
cooling coils are checked by your dealer.
4. Slide the black plastic filter retainer towards you and
remove.
5. Remove filters by pulling toward you and away from the
filter track.
6. A filter removal rod is shipped taped to the partition
located near the bottom filter track. The filter removal rod
will aid in the removal of filters beyond the reach of the
service person.
Compressor — All compressors are factory supplied with
a normal charge of the correct type of refrigeration-grade oil in
them and should not require additional oil.
Condenser Fan
WARNING
7. Inspect or replace filters.
8. Return filters to filter tracks. Note direction of airflow
arrows on filter frame.
Do not poke sticks, screwdrivers, or any other object into
revolving fan blades. Severe bodily injury may result.
9. Reinstall the black plastic filter retainer.
10. Place the filter removal rod back on the partition for
future use.
11. Reinstall inner panel.
12. Reinstall bolt securing the inner panel.
The fan must be kept free of all obstructions to ensure prop-
er cooling. Contact your dealer for any required service.
Electrical Controls and Wiring — Electrical con-
trols are difficult to check without proper instrumentation. If
there are any discrepancies in the operating cycle, contact your
dealer and request service.
13. Close filter access panel and tighten latches.
If you have difficulty in locating your air filter or if you
have questions concerning proper filter maintenance, contact
your dealer for instructions. When replacing your unit filters,
always use the same size and type of filter that was originally
supplied by the installer.
Units with outdoor air capability have a cleanable filter for
the outdoor air. This filter should be checked annually and
cleaned as necessary with steam or hot water and a mild deter-
gent. Do not use throwaway filters in place of cleanable filters.
Refrigerant Circuit — The refrigerant circuit is difficult
to check for leaks without the proper equipment. If inadequate
cooling is suspected, contact your local dealer for service.
Combustion Area and Vent System — The com-
bustion area and vent system should be visually inspected be-
fore each heating season. The normal accumulation of dirt,
soot, rust, and scale can result in loss of efficiency and im-
proper performance if allowed to build up.
WARNING
Never operate your unit without filters in place. Failure to
heed this warning may result in damage to the blower
motor and/or compressor. An accumulation of dust and lint
on internal parts of your unit can cause loss of efficiency
and, in some cases, fire.
CAUTION
If your unit makes any unusual or especially loud noises
during heating, shut down the heating section and call your
dealer.
Heat Exchanger — To ensure dependable and efficient
heating operation, the heat exchanger should be checked by a
qualified maintenance person before each heating season and
cleaned when necessary. This checkout should not be attempt-
ed by anyone not having the required expertise and equipment
to do the job properly. Checking and/or cleaning the heat
exchanger involves removing the gas controls assembly, the
flue collector box, and the flue collector box cover. When
finished, the gas controls assembly must be reinstalled for
proper operation. Also, the flue collector box cover must be
replaced correctly so that a proper seal is maintained. Refer to
unit installation instructions for correct procedure. Contact
your dealer for the required periodic maintenance.
See Fig. 1 and 2 and proceed as follows to inspect the com-
bustion area and power-venting system of your unit.
1. Turn off gas supply to your unit.
2. Turn off electrical power to your unit.
3. Remove gas section access panels.
4. Using a flashlight, carefully inspect the burner areas for
dirt, soot, rust, or scale.
CAUTION
If dirt, soot, rust, or scale accumulations are found, call
your dealer and do not operate your heating section.
Fans and Belts — Periodically check the condition of
the fan wheels and housings, and belt tension. When service is
necessary, call your dealer.
5. When you have completed your inspection, follow the To
Light Unit section in this manual to restore your unit to
operation.
6
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6. Observe unit heating operation. Watch the burner flame
to see if it is bright blue. If you observe a suspected mal-
function or if the flame is not bright blue, call your dealer.
Complete service instructions can be found in the unit
Controls, Start-Up, Operation, Service and Troubleshooting
literature.
WARNING
BEFORE YOU CALL FOR SERVICE,
CHECK FOR PROBLEMS
Components in heat section may be hot after unit has been
started. When observing flame, be careful not to get close
to or touch heating components. Serious personal injury
may result.
THAT CAN BE EASILY SOLVED
If insufficient heating or cooling is suspected:
(
) Check for sufficient airflow. Check the air filter for dirt.
Check for blocked return or supply-air grilles. Be sure they are
open and unobstructed. If these checks do not reveal the cause,
call your servicing dealer.
If your unit is not operating at all, check the following list
for easy solutions:
7. Replace gas section access panels.
Unit Panels — After performing any maintenance or
service on the unit, be sure all panels are securely fastened in
place to prevent rain from entering unit cabinet and to prevent
disruption of the correct unit airflow pattern.
(
) If using a thermostat, check to be sure that your thermo-
stat temperature set point is above the indoor temperature dur-
ing the heating season, or below the indoor temperature during
the cooling season. Be sure the thermostat mode is in the
proper AUTO, HEAT, or COOL mode and not in the OFF
mode.
REGULAR DEALER MAINTENANCE
In addition to the type of routine maintenance you might be
willing to perform, your unit should be inspected regularly by a
properly trained service technician. An inspection (preferably
each year, but at least every other year) should include the
following:
(
) Check scrolling marquee to be sure unit is not in Service
Test mode and that unit has not been disabled. Check set points
are properly set.
1. Inspection of all flue product passages — including the
burners, heat exchanger, and flue collector box.
2. Inspection of all combustion and ventilation-air passages
and openings.
3. Close inspection of all gas pipes leading to and inside
your unit.
4. Inspection and if required, cleaning of the condenser and
evaporator coils.
5. Inspection and if required, cleaning of the condensate
drain pan.
6. Inspection and cleaning of blower wheel housing and
motor.
7. Inspection of all supply and return-air ducts for leaks, ob-
structions, and insulation integrity. Any problems found
should be resolved at the time of inspection.
8. Inspection of the unit base for cracks, gaps, etc., which
may cause a hazardous condition.
(
) Is the electrical supply switch ON? Are any fuses blown
or has the circuit breaker tripped?
) During the heating season, check the external manual
(
shutoff valve. Is this lever parallel with the pipe, indicating that
the valve is open? Or is the lever at the right angle, indicating
that the valve is closed? If closed, has the gas been shut off for
safety reasons? Otherwise, you may open the valve and follow
the start-up procedures listed in this manual.
NOTE: Before proceeding with the next check, turn OFF the
electrical power supply to the unit. Remove the gas section
access panels.
(
) During the heating season, check the switch on the gas
valve. Is it in the ON position? If it is not, be sure it has not
been turned off for the purpose of safety. If no safety hazards
are present, follow the start-up procedures in this manual.
(
) If your unit still fails to operate, call your servicing dealer
for troubleshooting and repairs. Specify the model and serial
numbers of your unit. (Record them in this manual in the space
provided.) If the dealer knows exactly which unit you have,
he may be able to offer suggestions over the phone, or save
valuable time through knowledgeable preparation for the
service call.
9. Inspection of the unit casing for signs of deterioration.
10. Inspection of all electrical wiring and components to
ensure proper connection.
11. Inspection for leaks in the refrigerant circuit. Pressure-
check to determine appropriate refrigerant charge.
IN CASE OF TROUBLE
12. Inspection of fan wheels and housings, belt tension, and
fan motor shaft bearings.
If, after performing the above checks, unit performance is
unsatisfactory, shut off the unit and call your dealer.
13. Operational check of the unit to determine working
conditions. Repair or adjustment should be made at the
time of inspection.
Your servicing dealer may offer an economical service con-
tract that covers seasonal inspections. Ask for further details.
Dealer’s Name _____________________________________
Telephone No. _____________________________________
Unit Model _______________________________________
Unit Serial Number _________________________________
7
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Copyright 2008 Carrier Corporation
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Catalog No. 04-53480052-01
Printed in U.S.A.
Form 48A-5SO
Pg 8
3-08
Replaces: 48A-3SO
Book 1
Tab 1a
Download from Www.Somanuals.com. All Manuals Search And Download.
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