Bryant Furnace 355M 40 4 User Manual

installation, start-up,

355MAV

Series D

and operating instructions

DELUXE 4-WAY MULTIPOISE

VARIABLE-CAPACITY DIRECT-VENT

CONDENSING GAS FURNACE

Cancels: II 355M-40-4

II 355M-40-5

7-97

CANADIAN GAS ASSOCIATION

ama

A PPROVED

A93040

NOTE: Read the entire instruction manual before starting the

installation.

As an ENERGY STAR^SM

Partner, Bryant Heating &

Cooling Systems Com-

pany has determined that

this product meets the EN-

ERGY STAR guidelines

for energy efficiency.

This symbol → indicates a change since the last issue.

CERTIFICATION OF MANUFACTURING SITE

Index

Page

DIMENSIONAL DRAWING........................................................2

SAFETY CONSIDERATIONS.....................................................3

Clearances to Combustibles......................................................3

ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS ....3-4

INTRODUCTION..........................................................................4

APPLICATIONS ......................................................................4-11

General ......................................................................................4

Upflow Applications..............................................................4-6

Downflow Applications.........................................................7-8

Horizontal Left (Supply-Air Discharge) Applications .........8-9

Horizontal Right (Supply-Air Discharge) Applications.....9-11

LOCATION ............................................................................11-13

General...............................................................................11-12

Low-Fire Only Installation.....................................................12

Furnace Location Relative to Cooling Equipment ................12

Hazardous Locations...............................................................13

INSTALLATION....................................................................13-17

Leveling Legs (If Desired).....................................................13

Installation In Upflow or Downflow Applications ..........13-15

Installation In Horizontal Applications..................................15

Filter Arrangement..................................................................16

Bottom Closure Panel.............................................................16

Gas Piping...............................................................................17

ELECTRICAL CONNECTIONS...........................................17-21

115-v Wiring......................................................................17-18

24-v Wiring........................................................................18-20

Accessories ........................................................................20-21

DIRECT VENTING ...............................................................21-29

Removal of Existing Furnaces from

AIRFLOW

UPFLOW

HORIZONTAL

LEFT

HORIZONTAL

RIGHT

DOWNFLOW

AIRFLOW

A93041

Fig. 1—Multipoise Orientations

Heating Mode—Two Stage....................................................32

Emergency Heat Mode...........................................................32

Cooling Mode .........................................................................32

Heat Pump Mode...............................................................32-33

Continuous Fan Mode ............................................................33

Component Test......................................................................34

Bypass Humidifier Mode........................................................34

Dehumidification Mode..........................................................34

Zone Mode..............................................................................34

START-UP PROCEDURES ..................................................34-42

General ....................................................................................34

Select Setup Switch Positions...........................................34-35

Prime Condensate Trap With Water.................................35-36

Purge Gas Lines......................................................................37

Adjustments .......................................................................37-42

Set Gas Input Rate ............................................................37-41

Set Temperature Rise ........................................................41-42

Set Thermostat Heat Anticipator............................................42

CHECK SAFETY CONTROLS ............................................42-43

Check Primary Limit Control.................................................42

Check Pressure Switch......................................................42-43

CHECKLIST...........................................................................43-44

Common Vent Systems.....................................................21

Combustion-Air and Vent Piping .....................................21-26

Concentric Vent and Combustion-Air Termination

Kit Installation..............................................................26-29

Multiventing and Vent Terminations.....................................29

CONDENSATE DRAIN..............................................................29

General ....................................................................................29

Application..............................................................................29

Condensate Drain Protection..................................................29

SEQUENCE OF OPERATION..............................................31-34

Self-Test Mode........................................................................31

Heating Mode ....................................................................31-32

—1—

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SAFETY CONSIDERATIONS

identify unsafe practices which would result in minor personal

injury or product and property damage. NOTE is used to highlight

suggestions which will result in enhanced installation, reliability,

or operation.

Installing and servicing heating equipment can be hazardous due to

gas and electrical components. Only trained and qualified person-

nel should install, repair, or service heating equipment. Untrained

personnel can perform basic maintenance functions such as clean-

ing and replacing air filters. All other operations must be per-

formed by trained service personnel. When working on heating

equipment, observe precautions in literature, on tags, and on labels

attached to or shipped with unit and other safety precautions that

may apply.

ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS

CAUTION: Electrostatic discharge can affect electronic

components. Take precautions during furnace installation

and servicing to protect the furnace electronic control.

Precautions will prevent electrostatic discharges from

personnel and hand tools which are held during the

procedure. These precautions will help to avoid exposing

the control to electrostatic discharge by putting the

furnace, the control, and the person at the same electro-

static potential.

→ ^{Follow all safety codes. In the United States, follow all safety}

codes including the National Fuel Gas Code (NFGC) NFPA No.

54-1996/ANSI Z223.1-1996 and the Installation Standards, Warm

Air Heating and Air Conditioning Systems (NFPA 90B)

ANSI/NFPA 90B. In Canada, refer to the current edition of the

National Standard of Canada CAN/CGA-B149.1- and .2-M95

Natural Gas and Propane Installation Codes (NSCNGPIC). Wear

safety glasses and work gloves. Have fire extinguisher available

during start-up and adjustment procedures and service calls.

1. Disconnect all power to the furnace. DO NOT TOUCH

THE CONTROL OR ANY WIRE CONNECTED TO THE

CONTROL PRIOR TO DISCHARGING YOUR BODY’S

ELECTROSTATIC CHARGE TO GROUND.

Recognize safety information. This is the safety-alert symbol

When you see this symbol on unit or in instructions and manuals,

be alert to potential for personal injury.

2. Firmly touch a clean, unpainted, metal surface of the

furnace chassis which is close to the control. Tools held in

a person’s hand during grounding will be satisfactorily

discharged.

Understand the signal words DANGER, WARNING, and CAU-

TION. These words are used with safety-alert symbol. DANGER

identifies the most serious hazards which will result in severe

personal injury or death. WARNING signifies hazards which

could result in personal injury or death. CAUTION is used to

3. After touching the chassis you may proceed to service the

control or connecting wires as long as you do nothing that

This forced air furnace is equipped for use with natural gas at altitudes 0 - 10,000 ft (0 - 3,050m), except 140 size

Furnaces are only approved for altitudes 0 - 7,000 ft. (0 - 2,135m).

An accessory kit, supplied by the manufacturer, shall be used to convert to propane gas use or may be required for

some natural gas applications.

This furnace is for indoor installation in a building constructed on site. This furnace may be installed in a manufactured

(mobile) home when stated on rating plate and using factory authorized kit.

This furnace may be installed on combustible flooring in alcove or closet at minimum clearance from combustible

material.

This appliance requires a special venting system. Refer to the installation instructions for parts list and method of

installation. This furnace is for use with schedule-40 PVC, PVC-DWV, or ABS-DWV pipe, and must not be vented in

common with other gas-fired appliances. Construction through which vent/air intake pipes may be installed is maximum

24 inches (600 mm), minimum 3/4 inches (19 mm) thickness (including roofing materials).

MINIMUM INCHES CLEARANCE

Clearance arrows

do not change with

furnace orientation.

TO COMBUSTIBLE CONSTRUCTION

ALL POSITIONS:

Mimimum front clearance for service 30

inches (762mm).

140 size furnaces require 1 inch back

clearance to combustible materials.

††

DOWNFLOW POSITIONS:

For installation on combustible floors only

†

††

when installed on special base No.

KGASB0201ALL, Coil Assembly, Part No.

CD5 or CK5, or Coil Casing, Part No.

KCAKC.

0"_{B A}

HORIZONTAL POSITIONS:

Clearance shown is for air inlet and air

outlet end.

Line contact is permissible only between

lines formed by intersections of top and two

sides of furnace jacket, and building joists,

studs, or framing.

MIN

120 and 140 size Furnaces require 1 inch

bottom clearance to combustible materials.

†

Vent clearance to

combustibles 0".

323857-101 REV. B (LIT)

Clearance in inches

A97378

→ Fig. 3—Clearances to Combustibles

—3—

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recharges your body with static electricity (for example; DO

NOT move or shuffle your feet, DO NOT touch un-

grounded objects, etc.).

Installations must comply with regulations of serving gas supplier

and local building, heating, plumbing, or other codes in effect in

area in which installation is made. In absence of local codes,

installation must conform with NFGC.

4. If you touch ungrounded objects (recharge your body with

static electricity), firmly touch furnace again before touch-

ing control or wires.

Canadian installations must be made in accordance with NSCNG-

PIC and all authorities having jurisdiction.

5. Use this procedure for installed and uninstalled (un-

grounded) furnaces.

These instructions cover minimum requirements for a safe instal-

lation and conform to existing national standards and safety codes.

In some instances, these instructions exceed certain local codes

and ordinances, especially those that may not have kept pace with

changing residential construction practices. We require these

instructions as a minimum for a safe installation.

6. Before removing a new control from its container, dis-

charge your body’s electrostatic charge to ground to protect

the control from damage. If the control is to be installed in

a furnace, follow items 1 through 5 before bringing the

control or yourself into contact with the furnace. Put all

used AND new controls into containers before touching

ungrounded objects.

CAUTION: Application of this furnace should be in-

doors with special attention given to vent sizing and

material, gas input rate, air temperature rise, unit leveling,

and unit sizing. Improper installation or misapplication of

furnace can require excessive servicing or cause prema-

ture component failure.

7. An ESD service kit (available from commercial sources)

may also be used to prevent ESD damage.

INTRODUCTION

The 355MAV Multipoise Condensing Gas-Fired Furnaces are

A.G.A./C.G.A. certified for natural and propane gases and for

installation in alcoves, attics, basements, closets, utility rooms,

crawlspaces, and garages. The furnace is factory-shipped for use

with natural gas. An A.G.A./C.G.A. listed gas conversion kit is

required to convert furnace for use with propane gas.

These furnaces SHALL NOT be installed directly on carpeting,

tile, or any other combustible material other than wood flooring. In

downflow installations, accessory floor base MUST be used when

installed on combustible materials and wood flooring. Special base

is not required when this furnace is installed on manufacturer’s

Coil Assembly Part No. CD5 or CK5, or when Coil Box Part No.

KCAKC is used. The design of this furnace line is not

A.G.A./C.G.A. certified for installation in mobile homes, recre-

ation vehicles, or outdoors. These furnaces are suitable for

installation in a residence built on site or a manufactured residence

completed at final site.

These furnaces are shipped with the drain and pressure tubes

connected for UPFLOW applications. Minor modifications are

required when used in DOWNFLOW, HORIZONTAL RIGHT, or

HORIZONTAL LEFT (supply-air discharge direction) applica-

tions as shown in Fig. 1. See details in Applications section.

These furnaces are shipped with the following materials to assist in

proper furnace installation. These materials are shipped in the main

blower compartment.

WARNING: Improper installation, adjustment, alter-

ation, service, maintenance, or use can cause carbon

monoxide poisoning, explosion, fire, electrical shock, or

other conditions which may cause personal injury or

property damage. Consult a qualified installer, service

agency, local gas supplier, or your distributor or branch

for information or assistance. The qualified installer or

agency must use only factory-authorized and listed kits or

accessories when modifying this product. Failure to

follow this warning could result in electrical shock, fire,

personal injury, or death.

For accessory installation details, refer to applicable installation

literature.

APPLICATIONS

I. GENERAL

Some assembly and modifications are required for furnaces

installed in any of the 4 applications shown in Fig. 1. All drain and

pressure tubes are connected as shown in Fig. 5. See appropriate

application instructions for these procedures.

Installer Packet includes:

II. UPFLOW APPLICATIONS

Installation, Start-Up, and Operating Instructions

An upflow furnace application is where furnace blower is located

below combustion and controls section of furnace, and conditioned

air is discharged upwards.

Service and Maintenance Procedures

User’s Information Manual

Warranty Certificate

Loose Parts Bag includes:

Quantity

A. Condensate Trap Location (Factory-Shipped

Orientation)

Pressure tube extension

Collector box or condensate trap extension tube

Inducer housing drain tube

1/2-in. CPVC street elbow

Drain tube coupling

Drain tube coupling grommet

Vent and combustion-air pipe support

Combustion-air pipe perforated disk assembly

The condensate trap is factory installed in the blower shelf and

factory connected for UPFLOW applications. A factory-supplied

tube is used to extend the condensate trap drain connection to the

desired furnace side for field drain attachment. See Condensate

Trap Tubing (Factory-Shipped Orientation) section for drain tube

extension details.

→ ^{Before installing the furnace in the United States, refer to the}

current edition of the NFGC and the NFPA 90B. For further

information, the NFGC and the NFPA 90B are available from

National Fire Protection Association Inc., Batterymarch Park,

Quincy, MA 02269; American Gas Association, 1515 Wilson

Boulevard, Arlington, VA 22209; or from Literature Distribution.

Before installing the furnace in Canada, refer to the current edition

of the NSCNGPIC. Contact Standards Department of Canadian

Gas Association, 55 Scarsdale Road, Don Mills, Ontario, Canada

M3B 2R3.

B. Condensate Trap Tubing (Factory-Shipped

Orientation)

NOTE: See Fig. 5 or tube routing label on main furnace door to

confirm location of these tubes.

1. Collector Box Drain, Inducer Housing Drain, Relief Port,

and Pressure Switch Tubes

These tubes should be factory attached to condensate trap

and pressure switch ready for use in UPFLOW applications.

These tubes can be identified by their connection location

—4—

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FURNACE

DOOR

BLOWER SHELF

CONDENSATE

TRAP

FURNACE

DOOR

CONDENSATE

TRAP (INSIDE)

FURNACE

SIDE

FURNACE

SIDE

FIELD

DRAIN

CONN

FIELD

DRAIN

CONN

ALTERNATE DRAIN

TUBE LOCATION

SIDE VIEW

FRONT VIEW

END VIEW

FRONT VIEW

CONDENSATE TRAP

DRAIN TUBE LOCATION

HORIZONTAL

APPLICATIONS

DOWNFLOW AND ALTERNATE

EXTERNAL UPFLOW APPLICATIONS

UPFLOW APPLICATIONS

SLOT FOR SCREW

HORIZONTAL

APPLICATION

(OPTIONAL)

¹⁄4 OD

COLLECTOR BOX TO

TRAP RELIEF PORT

¹⁄2 OD

INDUCER HOUSING

DRAIN CONNECTION

⁵⁄8 OD

COLLECTOR BOX

DRAIN CONNECTION

SCREW HOLE FOR

UPFLOW OR DOWN-

FLOW APPLICATIONS

(OPTIONAL)

WIRE TIE

GUIDES

(WHEN USED)

¹⁄2-IN. PVC OR CPVC

FRONT VIEW

SIDE VIEW

A93026

Fig. 4—Condensate Trap

and also by a color label on each tube. These tubes are

identified as follows: collector box drain tube (blue label),

inducer housing drain tube (violet label or molded), relief

port tube (green label), and pressure switch tube (pink

label).

f. Connect larger diameter drain tube and clamp (factory-

supplied in loose parts bag) to condensate trap and clamp

securely.

g. Route tube to coupling and cut to appropriate length.

h. Attach tube to coupling and clamp securely.

2. Condensate Trap Drain Tube

C. Condensate Trap Location (Alternate Upflow

Orientation)

The condensate trap drain connection must be extended for

field attachment by doing the following:

An alternate location for the condensate trap is the left-hand side

of casing. (See Fig. 2 and 6.)

a. Determine location of field drain connection. (See Fig. 2

or 5.)

NOTE: If the alternate left-hand side of casing location is used,

the factory-connected drain and relief port tubes must be discon-

nected and modified for attachment. See Condensate Trap Tubing

(Alternate Upflow Orientation) section for tubing attachment.

NOTE: If internal filter is used, drain tube should be located to

opposite side of casing of return duct attachment to assist in filter

removal.

b. Remove and discard casing drain hole plug button from

desired side.

To relocate condensate trap to the left-hand side, perform the

following:

c. Install drain tube coupling grommet (factory-supplied in

loose parts bag) in selected casing hole.

1. Remove 3 tubes connected to condensate trap.

2. Remove trap from blower shelf by gently pushing tabs

inward and rotating trap.

d. Slide drain tube coupling (factory-supplied in loose parts

bag) through grommet so long end of coupling faces

blower.

3. Remove casing hole filler cap from casing hole. (See Fig. 2

or 6.)

e. Cement 2 factory-supplied 1/2-in. street CPVC elbows to

rigid drain tube connection on condensate trap. (See Fig.

5.) These elbows must be cemented together and ce-

mented to condensate trap drain connection.

4. Install casing hole filler cap into blower shelf hole where

trap was removed.

5. Install condensate trap into left-hand side casing hole by

inserting tube connection stubs through casing hole and

rotating until tabs snap into locking position.

NOTE: Failure to use CPVC elbows may allow drain to kink,

preventing draining.

—5—

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PLUG

CAP

PLUG

CAP

COLLECTOR BOX

DRAIN TUBE (BLUE

& WHITE STRIPED)

COLLECTOR BOX

DRAIN TUBE (BLUE

& WHITE STRIPED)

COLLECTOR BOX

TUBE (PINK)

COLLECTOR BOX

TUBE (PINK)

COLLECTOR BOX

TUBE (GREEN)

COLLECTOR BOX

DRAIN TUBE (GREEN)

INDUCER HOUSING

(MOLDED) DRAIN

TUBE (BEHIND

COLLECTOR BOX

DRAIN TUBE)

CONDENSATE

TRAP

COLLECTOR BOX

DRAIN TUBE (BLUE)

CONDENSATE

TRAP

COLLECTOR BOX

TUBE (GREEN)

INDUCER

HOUSING

DRAIN TUBE

(VIOLET)

FIELD-INSTALLED

FACTORY-SUPPLIED

DRAIN TUBE

COUPLING (LEFT

DRAIN OPTION)

FIELD-INSTALLED

FACTORY-SUPPLIED

DRAIN TUBE

FIELD-INSTALLED

FACTORY-SUPPLIED

¹⁄2 -IN. CPVC STREET

ELBOWS (2) FOR

FACTORY-SUPPLIED

DRAIN TUBE

COUPLING (RIGHT

DRAIN OPTION)

LEFT DRAIN OPTION

A94213

A94214

Fig. 5—Factory-Shipped Upflow Tube Configuration

(Shown With Blower Access Panel Removed)

Fig. 6—Alternate Upflow Tube Configuration and

Trap Location

D. Condensate Trap Tubing (Alternate Upflow

Orientation)

c. Determine appropriate length, cut, and connect tube.

E. Condensate Trap Field Drain Attachment

NOTE: See Fig. 6 or tube routing label on main furnace door to

confirm location of these tubes.

Refer to Condensate Drain section for recommendations and

procedures.

1. Collector Box Drain Tube

F. Pressure Switch Tubing

Connect collector box drain tube (blue label) to condensate

trap.

The LOWER collector box pressure tube (pink label) is factory

connected to the pressure switch and should not require any

modification.

NOTE: On 17-1/2-in. wide furnaces ONLY, cut tube between

corrugated sections to prevent kinks.

NOTE: See Fig. 5 or 6 or tube routing label on main furnace door

to check for proper connections.

2. Inducer Housing Drain Tube

a. Remove and discard LOWER (molded) inducer housing

drain tube which was previously connected to conden-

sate trap.

G. Upper Collector Box and Inducer Housing (Unused)

Drain Connections

UPPER COLLECTOR BOX DRAIN CONNECTION

b. Use inducer housing drain extension tube (violet label

and factory-supplied in loose parts bag) to connect

LOWER inducer housing drain connection to conden-

sate trap.

Attached to the UPPER collector box drain connection is a

factory-installed corrugated, plugged tube (blue and white striped

label). This tube is plugged to prevent condensate leakage in this

application. Ensure this tube is plugged.

c. Determine appropriate length, cut, and connect tube.

d. Clamp tube to prevent any condensate leakage.

NOTE: See Fig. 5 or 6 or tube routing label on main furnace door

to check for proper connections.

3. Relief Port Tube

UPPER INDUCER HOUSING DRAIN CONNECTION

a. Connect relief port tube (green label) to condensate trap.

Attached to the UPPER (unused) inducer housing drain connection

is a cap and clamp. This cap is used to prevent condensate leakage

in this application. Ensure this connection is capped.

b. Extend this tube (if required) by splicing to small

diameter tube (factory-supplied in loose parts bag).

—6—

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COLLECTOR BOX

DRAIN TUBE (BLUE)

CAP

COLLECTOR BOX

TUBE (GREEN)

PLUG

CAP

COLLECTOR BOX

TUBE (GREEN)

COLLECTOR BOX

DRAIN TUBE (BLUE)

COLLECTOR BOX

TUBE (PINK)

COLLECTOR BOX

TUBE (PINK)

COLLECTOR BOX

DRAIN TUBE (BLUE

& WHITE STRIPED)

COLLECTOR BOX

DRAIN TUBE (BLUE

& WHITE STRIPED)

COLLECTOR BOX

EXTENSION TUBE

COLLECTOR BOX

EXTENSION TUBE

INDUCER HOUSING

DRAIN TUBE

(VIOLET)

CONDENSATE

TRAP

CONDENSATE

TRAP

COLLECTOR BOX

EXTENSION

DRAIN TUBE

INDUCER HOUSING

DRAIN TUBE (VIOLET)

DRAIN TUBE

COUPLING

A94215

A94216

Fig. 7—Downflow Tube Configuration

(Left-Hand Trap Installation)

Fig. 8—Downflow Tube Configuration

(Right-Hand Trap Installation)

NOTE: See Fig. 5 or 6 or tube routing label on main furnace door

to check for proper connections.

a. Remove factory-installed plug from LOWER collector

box drain tube (blue and white striped label).

b. Install removed clamp and plug into UPPER collector

box drain tube (blue label) which was connected to

condensate trap.

H. Condensate Trap Freeze Protection

Refer to Condensate Drain Protection section for recommenda-

tions and procedures.

c. Connect LOWER collector box drain connection to

condensate trap.

III. DOWNFLOW APPLICATIONS

A downflow furnace application is where furnace blower is located

above combustion and controls section of furnace, and conditioned

air is discharged downwards.

(1.) Condensate Trap Located on Left Side of Casing

(a.) Connect LOWER collector box drain tube

(blue and white striped label) to condensate

trap. Tube does not need to be cut.

A. Condensate Trap Location

The condensate trap must be removed from the factory-installed

blower shelf location and relocated in selected application location

as shown in Fig. 2, 7, or 8.

(b.) Clamp tube to prevent any condensate leakage.

(2.) Condensate Trap Located on Right Side of Casing

To relocate condensate trap from the blower shelf to desired

location, perform the following:

(a.) Install drain tube coupling (factory-supplied in

loose parts bag) into collector box drain tube

(blue and white striped label) which was pre-

viously plugged.

1. Remove 3 tubes connected to condensate trap.

2. Remove trap from blower shelf by gently pushing tabs

inward and rotating trap.

(b.) Connect larger diameter drain tube (factory-

supplied in loose parts bag) to drain tube

coupling, extending collector box drain tube

for connection to condensate trap.

3. Remove casing hole filler cap from casing hole. (See Fig. 2,

7, or 8.)

4. Install casing hole filler cap into blower shelf hole where

trap was removed.

→

(c.) Route extended collector box drain tube di-

rectly from collector box drain to condensate

trap as shown in Fig. 8.

5. Install condensate trap into desired casing hole by inserting

tube connection stubs through casing hole and rotating until

tabs snap into locking position.

(d.) Determine appropriate length and cut.

(e.) Connect to condensate trap.

B. Condensate Trap Tubing

(f.) Clamp tube to prevent any condensate leakage.

NOTE: See Fig. 7 or 8 or tube routing label on main furnace door

to check for proper connections.

2. Inducer Housing Drain Tube

a. Remove factory-installed cap and clamp from LOWER

inducer housing drain connection.

1. Collector Box Drain Tube

—7—

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b. Remove and discard UPPER (molded) inducer housing

drain tube which was previously connected to conden-

sate trap.

IV. HORIZONTAL LEFT (SUPPLY-AIR DISCHARGE)

APPLICATIONS

A horizontal left furnace application is where furnace blower is

located to the right of combustion and controls section of furnace,

and conditioned air is discharged to the left.

c. Install cap and clamp on UPPER inducer housing drain

connection where molded drain tube was removed.

d. Use inducer housing drain tube (violet label and factory-

supplied in loose parts bag) to connect LOWER inducer

housing drain connection to the condensate trap.

CAUTION: Local codes may require a drain pan under

entire furnace and condensate trap when a condensing

furnace is used in an attic application or over a finished

ceiling.

e. Connect inducer housing drain connection to condensate

trap.

(1.) Condensate Trap Located on Left Side of Casing

(a.) Determine appropriate length and cut.

(b.) Connect tube to condensate trap.

NOTE: In Canada, installations shall be in accordance with

current NSCNGPIC and/or local codes.

NOTE: The auxiliary junction box (J-box) MUST be relocated to

opposite side of furnace casing. (See Fig. 9.) See Electrical

Connection section for J-box relocation.

(c.) Clamp tube to prevent any condensate leakage.

(2.) Condensate Trap Located on Right Side of Casing

A. Condensate Trap Location

→

(a.) Route inducer housing drain tube (violet label)

directly from inducer housing drain to conden-

sate trap as shown in Fig. 8.

The condensate trap must be removed from the factory-installed

blower shelf location and relocated in selected application location

as shown in Fig. 2 or 9.

(b.) Determine appropriate length and cut.

(c.) Connect tube to condensate trap.

To relocate condensate trap from the blower shelf to desired

location, perform the following:

(d.) Clamp tube to prevent any condensate leakage.

1. Remove 3 tubes connected to condensate trap.

3. Relief Port Tube

2. Remove trap from blower shelf by gently pushing tabs

inward and rotating trap.

Refer to Pressure Switch Tubing section for connection

procedure.

3. Remove casing hole filler cap from casing hole. (See Fig. 2

or 9.)

C. Condensate Trap Field Drain Attachment

4. Install casing hole filler cap into blower shelf hole where

trap was removed.

Refer to Condensate Drain section for recommendations and

procedures.

5. Install condensate trap into casing hole by inserting tube

connection stubs through casing hole and rotating until tabs

snap into locking position.

D. Pressure Switch Tubing

One collector box pressure tube (pink label) is factory connected to

the pressure switch for use when furnace is installed in UPFLOW

or HORIZONTAL LEFT applications. This tube MUST be dis-

connected and used for the condensate trap relief port tube. The

other collector box pressure tube (green label) which was factory

connected to the condensate trap relief port connection MUST be

connected to the pressure switch in DOWNFLOW or HORIZON-

TAL RIGHT applications.

B. Condensate Trap Tubing

NOTE: See Fig. 9 or tube routing label on main furnace door to

check for proper connections.

1. Collector Box Drain Tube

a. Install drain tube coupling (factory-supplied in loose

parts bag) into collector box drain tube (blue label)

which was previously connected to condensate trap.

NOTE: See Fig. 7 or 8 or tube routing label on main furnace door

to check for proper connections.

b. Connect large diameter drain tube and clamp (factory-

supplied in loose parts bag) to drain tube coupling,

extending collector box drain tube.

Relocate tubes as described below.

1. Disconnect collector box pressure tube (pink label) attached

to pressure switch.

c. Route extended tube (blue label) to condensate trap and

cut to appropriate length.

2. Extend collector box pressure tube (green label) which was

previously connected to condensate trap relief port connec-

tion by splicing to small diameter tube (factory-supplied in

loose parts bag).

d. Clamp tube to prevent any condensate leakage.

2. Inducer Housing Drain Tube

3. Connect collector box pressure tube (green label) to pres-

sure switch connection labeled COLLECTOR BOX.

a. Remove and discard LOWER (molded) inducer housing

drain tube which was previously connected to conden-

sate trap.

4. Extend collector box pressure tube (pink label) which was

previously connected to pressure switch by splicing to

remaining small diameter tube (factory-supplied in loose

parts bag).

b. Use inducer housing drain extension tube (violet label

and factory-supplied in loose parts bag) to connect

LOWER inducer housing drain connection to conden-

sate trap.

5. Route this extended tube (pink label) to condensate trap

relief port connection.

c. Determine appropriate length, cut, and connect tube.

d. Clamp tube to prevent any condensate leakage.

6. Determine appropriate length, cut, and connect tube.

7. Clamp tube to relief port connection.

3. Relief Port Tube

E. Condensate Trap Freeze Protection

a. Extend collector box tube (green label) which was

previously connected to condensate trap by splicing to

small diameter tube (factory-supplied in loose parts bag).

Refer to Condensate Drain Protection section for recommenda-

tions and procedures.

—8—

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b. Route extended collector box pressure tube to relief port

connection on condensate trap.

V. HORIZONTAL RIGHT (SUPPLY-AIR DISCHARGE)

APPLICATIONS

c. Determine appropriate length, cut, and connect tube.

d. Clamp tube to prevent any condensate leakage.

C. Condensate Trap Field Drain Attachment

A horizontal right furnace application is where furnace blower is

located to the left of combustion and controls section of furnace,

and conditioned air is discharged to the right.

Refer to Condensate Drain section for recommendations and

procedures.

D. Pressure Switch Tubing

CAUTION: Local codes may require a drain pan under

entire furnace and condensate trap when a condensing

furnace is used in attic application or over a finished

ceiling.

The LOWER collector box pressure tube (pink label) is factory

connected to the pressure switch and should not require any

modification.

NOTE: See Fig. 9 or tube routing label on main furnace door to

check for proper connections.

NOTE: In Canada, installations shall be in accordance with

current NSCNGPIC Installation Codes and/or local codes.

E. Condensate Trap Freeze Protection

A. Condensate Trap Location

Refer to Condensate Drain Protection section for recommenda-

tions and procedures.

F. Construct a Working Platform

The condensate trap must be removed from the factory-installed

blower shelf location and relocated in selected application location

as shown in Fig. 2 or 11.

Construct working platform where all required furnace clearances

are met. (See Fig. 3 and 10.)

To relocate condensate trap from the blower shelf to desired

location, perform the following:

1. Remove 3 tubes connected to condensate trap.

CAUTION: The condensate trap MUST be installed

below furnace. See Fig. 4 for dimensions. The drain

connection to condensate trap must also be properly

sloped to an open drain.

2. Remove trap from blower shelf by gently pushing tabs

inward and rotating trap.

3. Remove casing hole filler cap from casing hole. (See Fig. 2

or 11.)

NOTE: Combustion-air and vent pipes are restricted to a mini-

mum length of 5 ft. (See Table 6.)

NOTE: A 12-in. minimum offset pipe section is recommended

with short (5 to 8 ft) vent systems. This recommendation is to

reduce excessive condensate droplets from exiting the vent pipe.

(See Fig. 10 or 29.)

4. Install casing hole filler cap into blower shelf hole where

trap was removed.

5. Install condensate trap into casing hole by inserting tube

connection stubs through casing hole and rotating until tabs

snap into locking position.

PLUG

CAP

COLLECTOR BOX

AUXILIARY "J" BOX

RELOCATED HERE

DRAIN TUBE

(BLUE AND WHITE STRIPED)

CONDENSATE

TRAP

COLLECTOR BOX

TUBE (GREEN)

INDUCER HOUSING

COLLECTOR BOX

EXTENSION TUBE

DRAIN TUBE (VIOLET)

COLLECTOR BOX

DRAIN TUBE (BLUE)

COLLECTOR

BOX EXTENSION

DRAIN TUBE

DRAIN TUBE COUPLING

COLLECTOR BOX TUBE (PINK)

RELOCATE TUBE BETWEEN BLOWER SHELF AND INDUCER HOUSING FOR

040, 060, AND 080 HEATING INPUT FURNACES

A93353

Fig. 9—Horizontal Left Tube Configuration

—9—

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COMBUSTION – AIR

INTAKE

VENT

A 12-IN. MIN HORIZONTAL PIPE

SECTION IS RECOMMENDED WITH

SHORT (5 TO 8 FT) VENT SYSTEMS

TO REDUCE EXCESSIVE

CONDENSATE DROPLETS FROM

EXITING THE VENT PIPE.

30″ MIN

WORK AREA

5 ⁄ ″

MANUAL

SHUTOFF

GAS VALVE

ACCESS OPENING

FOR TRAP

DRAIN

SEDIMENT

TRAP

CONDENSATE

TRAP

NOTE: LOCAL CODES MAY REQUIRE A DRAIN PAN UNDER THE

FURNACE AND CONDENSATE TRAP WHEN A CONDENSING

FURNACE IS INSTALLED ABOVE FINISHED CEILINGS.

A93031

Fig. 10—Attic Location and Working Platform

B. Condensate Trap Tubing

3. Relief Port Tube

NOTE: See Fig. 11 or tube routing label on main furnace door to

check for proper connections.

Refer to Pressure Switch Tubing section for connection

procedure.

1. Collector Box Drain Tube

C. Condensate Trap Field Drain Attachment

a. Remove factory-installed plug from LOWER collector

box drain tube (blue and white striped label).

Refer to Condensate Drain section for recommendations and

procedures.

b. Install removed clamp and plug into UPPER collector

box drain tube (blue label) which was previously con-

nected to condensate trap.

D. Pressure Switch Tubing

One collector box pressure tube (pink label) is factory connected to

the pressure switch for use when furnace is installed in UPFLOW

or HORIZONTAL LEFT applications. This tube MUST be dis-

connected and used for the condensate trap relief port tube. The

other collector box pressure tube (green label) which was factory

connected to the condensate trap relief port connection MUST be

connected to the pressure switch in DOWNFLOW or HORIZON-

TAL RIGHT applications.

c. Connect LOWER collector box drain tube (blue and

white striped label) to condensate trap. Tube does not

need to be cut.

d. Clamp tube to prevent any condensate leakage.

2. Inducer Housing Drain Tube

a. Remove factory-installed cap and clamp from LOWER

inducer housing drain connection.

NOTE: See Fig. 11 or tube routing label on main furnace door to

check for proper connections.

b. Remove and discard UPPER (molded) inducer housing

drain tube which was previously connected to conden-

sate trap.

Relocate tubes as described below.

1. Disconnect collector box pressure tube (pink label) attached

to pressure switch.

c. Install cap and clamp on UPPER inducer housing drain

connection where molded drain tube was removed.

2. Extend collector box pressure tube (green label) which was

previously connected to condensate trap relief port connec-

tion by splicing to small diameter tube (factory-supplied in

loose parts bag).

d. Use inducer housing drain extension tube (violet label

and factory-supplied in loose parts bag) to connect

LOWER inducer housing drain connection to conden-

sate trap.

3. Connect collector box pressure tube (green label) to pres-

sure switch connection labeled COLLECTOR BOX.

e. Determine appropriate length, cut, and connect tube to

condensate trap.

4. Use remaining small diameter tube (factory-supplied in

loose parts bag) to extend collector box pressure tube (pink

label) which was previously connected to pressure switch.

f. Clamp tube to prevent any condensate leakage.

—10—

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COLLECTOR BOX DRAIN TUBE (BLUE)

CAP

COLLECTOR BOX TUBE (GREEN)

COLLECTOR BOX TUBE (PINK)

PLUG

CONDENSATE

TRAP

COLLECTOR BOX DRAIN TUBE

(BLUE AND WHITE STRIPED)

INDUCER HOUSING

DRAIN TUBE (VIOLET)

COLLECTOR BOX

EXTENSION TUBE

A93354

Fig. 11—Horizontal Right Tube Configuration

5. Route this extended tube (pink label) to condensate trap

relief port connection.

6. Determine appropriate length, cut, and connect tube.

7. Clamp tube to relief port connection.

E. Condensate Trap Freeze Protection

LEVEL (0″)

FRONT

LEVEL (0″)

Refer to Condensate Drain Protection section for recommenda-

tions and procedures.

¹⁄2″ MAX

F. Construct a Working Platform

UPFLOW OR DOWNFLOW

HORIZONTAL

Construct working platform where all required furnace clearances

are met. (See Fig. 3 and 10.)

A93025

NOTE: For proper furnace operation, install furnace so that it is

level or pitched forward within 1/2 in. to ensure proper condensate

drainage from secondary heat exchangers.

CAUTION: The condensate trap MUST be installed

below furnace. See Fig. 4 for dimensions. The drain

connection to condensate trap must also be properly

sloped to an open drain.

Locate furnace as close to center of air distribution system as

possible.

Locate furnace so combustion-air pipe lengths are not exceeded.

Refer to Table 6.

NOTE: Combustion-air and vent pipes are restricted to a mini-

mum length of 5 ft. (See Table 6.)

CAUTION: If these furnaces are used during construc-

tion when adhesives, sealers, and/or new carpets are

being installed, make sure all combustion and circulating

air requirements are followed. If operation of furnace is

required during construction, use clean outside air for

combustion and ventilation. Compounds of chlorine and

fluorine, when burned with combustion air, form acids

which will cause corrosion of heat exchangers. Some of

these compounds are found in paneling, dry wall adhe-

sives, paints, thinners, masonry cleaning materials, and

many other solvents commonly used in the construction

process.

NOTE: A 12-in. minimum offset pipe section is recommended

with short (5 to 8 ft) vent systems. This recommendation is to

reduce excessive condensate droplets from exiting the vent pipe.

(See Fig. 10 or 29.)

LOCATION

I. GENERAL

When a furnace is installed so that supply ducts carry air to areas

outside the space containing the furnace, return air must also be

handled by ducts sealed to furnace casing. The ducts terminate

outside the space containing the furnace to ensure there will not be

a negative pressure condition within equipment room or space.

Furnace may be located in a confined space without special

provisions for dilution or ventilation air. This furnace must be

installed so electrical components are protected from water.

Excessive exposure to contaminated combustion air will

result in safety and performance related problems.

—11—

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FRONT

°F

32°F MINIMUM INSTALLED

AMBIENT OR FREEZE

PROTECTION REQUIRED

RETURN

AIR

MAX 85°F MIN 55°F

A93042

NOTE: These furnaces are designed for a minimum continuous

return-air temperature of 60°F or intermittent operation down to 55°F

such as when used with a night setback thermostat. Return-air

temperature must not exceed a maximum of 85°F. Failure to follow

these return-air temperature limits may affect reliability of heat

exchangers, motors, and controls.

A93058

CAUTION: If these furnaces are installed in an uncon-

ditioned space where ambient temperatures may be 32°F

or lower, freeze protection measures must be taken.

II. LOW-FIRE ONLY INSTALLATION

Provide ample space for servicing and cleaning. Always comply

with minimum fire protection clearances shown on unit’s clear-

ance to combustibles label. (See Fig. 3.) Locate furnace where

available electric power and gas supplies meet specifications on

furnace rating plate.

This 355MAV furnace can be installed to operate in the low-fire

only heating mode when sized using the low-fire heating capacity.

This is accomplished by placing setup switch SW-2 in the ON

position to provide only low-fire-heat operation. See Fig. 25 and

Table 10. With this setup, high-fire operation will not occur.

When the model no. on the furnace rating plate is followed by an

asterisk (*), the furnace has an alternate low-fire only efficiency

rating as listed in the GAMA and CEC directories. This alternate

rating will be listed as the furnace model number followed by an

(-L) suffix.

FRONT

CAUTION: The furnace can operate in the high-fire

mode when certain fault conditions occur. The following

precautions should be taken:

1. Size gas piping based on the high-fire input.

2. Check the high-fire input and adjust it per the main

literature instructions.

BACK

NEVER assume the high-fire input rate is not important

for low-fire-only installation.

III. FURNACE LOCATION RELATIVE TO COOLING

EQUIPMENT

FRONT

A93043

The cooling coil must be installed parallel with or on downstream

side of furnace to avoid condensation in heat exchanger. When

installed parallel with a furnace, dampers or other means used to

control flow of air must prevent chilled air from entering furnace.

If dampers are manually operated, they must be equipped with a

means to prevent operation of either unit unless damper is in

full-heat or full-cool position.

WARNING: Do not install furnace on its back. Safety

control operation will be adversely affected. Never con-

nect return-air ducts to back of furnace. Failure to follow

this warning could result in fire, personal injury, or death.

—12—

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IV. HAZARDOUS LOCATIONS

⁵⁄16″

1 ³⁄4″

⁵⁄16″

18-IN. MINIMUM

TO BURNERS

A93044

⁵⁄16″

1 ³⁄4″

WARNING: When furnace is installed in a residential

garage, it must be installed so that burners and ignition

sources are located a minimum of 18 in. above floor. The

furnace must be located or protected to avoid physical

damage by vehicles. When furnace is installed in a public

garage, airplane hangar, or other building having a

hazardous atmosphere, unit must be installed in accor-

dance with requirements of National Fire Protection

Association, Inc.

A89014

Fig. 12—Leveling Legs

1. Determine application being installed from Table 1.

2. Construct hole in floor per dimensions specified in Table 1

and Fig. 13.

INSTALLATION

I. LEVELING LEGS (IF DESIRED)

3. Construct plenum to dimensions specified in Table 1 and

Fig. 13.

When furnace is used in upflow position with side inlet(s), leveling

legs may be desired. (See Fig. 12.) Install field-supplied,

corrosion-resistant 5/16-in. machine bolts and nuts.

NOTE: The maximum length of bolt should not exceed 1-1/2 in.

1. Position furnace on its back. Locate and drill a 5/16-in.

diameter hole in each bottom corner of furnace. (See Fig.

12.) Holes in bottom closure panel may be used as guide

locations.

4. If downflow subbase (KGASB) is used, install as shown in

Fig. 14.

If coil assembly CD5 or CK5 or Coil Box KCAKC is used,

install as shown in Fig. 15.

NOTE: Remove furnace perforated, discharge duct flanges when

they interfere with mating flanges on coil on downflow subbase.

To remove furnace perforated, discharge duct flange, use wide

duct pliers or duct flange tool to bend flange back and forth until

it breaks off. Be careful of sharp edges. (See Fig. 16.)

2. For each hole, install nut on bolt and then install bolt and

nut in hole. (Install flat washer if desired.)

3. Install another nut on other side of furnace base. (Install flat

washer if desired.)

4. Adjust outside nut to provide desired height, and tighten

inside nut to secure arrangement.

WARNING: Do not bend duct flanges inward as shown

in Fig. 16. This will affect airflow across heat exchangers

and may cause limit cycling or premature heat exchanger

failure. Remove duct flange completely or bend it inward

a minimum of 210° as shown in Fig. 16.

NOTE: Bottom closure must be used when leveling legs are used.

See Bottom Closure Panel section.

II. INSTALLATION IN UPFLOW OR DOWNFLOW

APPLICATIONS

NOTE: This furnace is approved for use on combustible flooring

when special base (available from manufacturer) Part No.

KGASB0201ALL is used. Special base in not required when this

furnace is installed on manufacturer’s Coil Assembly Part No.

CD5 or CK5, or Coil Box Part No. KCAKC is used.

—13—

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PLENUM

OPENING

FLOOR

OPENING

A96283

Fig. 13—Floor and Plenum Opening Dimensions

FURNACE

(OR COIL CASING

WHEN USED)

CD5 OR CK5

COIL ASSEMBLY

OR KCAKC

COIL BOX

COMBUSTIBLE

FLOORING

COMBUSTIBLE

FLOORING

DOWNFLOW

SUBBASE

SHEET METAL

PLENUM

SHEET METAL

PLENUM

FLOOR

OPENING

FLOOR

OPENING

A96284

A96285

Fig. 15—Furnace, Plenum, and Coil

Assembly or Coil Box Installed

on a Combustible Floor

Fig. 14—Furnace, Plenum, and Subbase

Installed on a Combustible Floor

TABLE 1—OPENING DIMENSIONS (IN.)

FURNACE

CASING

WIDTH

PLENUM OPENING

FLOOR OPENING

APPLICATION

Upflow Applications

24-1/8

16-5/8

16-1/2

24-3/4

19-5/8

Downflow Applications on Non-Combustible Flooring

15-7/8

Downflow Applications on Combustible Flooring Using KGASB Subbase

Furnace with or without CD5 or CK5 Coil Assembly or KCAKC Coil Box

17-1/2

15-1/8

15-1/2

16-3/4

16-1/2

20-3/8

Downflow Applications on Combustible Flooring NOT Using KGASB Subbase

Furnace with CD5 or CK5 Coil Assembly or KCAKC Coil Box

Upflow Applications

19-1/2

19-3/8

24-1/8

20-1/8

24-3/4

19-5/8

Downflow Applications on Non-Combustible Flooring

Downflow Applications on Combustible Flooring Using KGASB Subbase

Furnace with or without CD5 or CK5 Coil Assembly or KCAKC Coil Box

18-5/8

20-1/4

20-3/8

Downflow Applications on Combustible Flooring NOT Using KGASB Subbase

Furnace with CD5 or CK5 Coil Assembly or KCAKC Coil Box

Upflow Applications

24-1/8

23-5/8

23-1/2

24-3/4

19-5/8

Downflow Applications on Non-Combustible Flooring

22-7/8

Downflow Applications on Combustible Flooring Using KGASB Subbase

Furnace with or without CD5 or CK5 Coil Assembly or KCAKC Coil Box

24-1/2

22-1/8

22-1/2

23-3/4

23-1/2

20-3/8

Downflow Applications on Combustible Flooring NOT Using KGASB Subbase

Furnace with CD5 or CK5 Coil Assembly or KCAKC Coil Box

—14—

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III. INSTALLATION IN HORIZONTAL APPLICATIONS

PERFORATED

DISCHARGE DUCT

FLANGE

These furnaces can be installed horizontally in either horizontal

left or right discharge position. In a crawlspace, furnace can either

be hung from floor joist or installed on suitable blocks or pad.

Furnace can be suspended from each corner by hanger bolts and

angle iron supports. (See Fig. 17.) Cut hanger bolts (4 each 3/8-in.

all-thread rod) to desired length. Use 1 X 3/8-in. flat washers,

3/8-in. lockwashers, and 3/8-in. nuts on hanger rods as shown in

Fig. 17. Dimples are provided for hole locations. (See Fig. 2.)

YES

CAUTION: The entire length of furnace MUST be

supported when furnace is used in a horizontal position to

ensure proper draining. When suspended, bottom brace

supports sides and center blower shelf. When unit is

supported from the ground, blocks or pad should support

sides and center blower shelf area.

210°

MIN

YES

A93029

Fig. 16—Duct Flanges

³⁄8-IN. ROD

ANGLE

5 ⁄ ″

IRON OR

EQUIVALENT

ALTERNATE SUPPORT

LOCATION 4-IN. MIN

8-IN. MAX

(B)

(A)

DRAIN

(B)

(A)

(B)

(A) ROD LOCATION

USING DIMPLE

LOCATORS

¹³/16-IN. MAX

ALTERNATE SUPPORT

LOCATION FROM BACK

³/8-IN. HEX NUT

& WASHER (4)

REQD PER ROD

(A)

(B)

(SEE DIMENSIONAL

DWG FOR

LOCATIONS)

NOTES: 1. A 1 In. clearance minimum between top of

(A) PREFERRED ROD LOCATION

(B) ALTERNATE ROD LOCATION

furnace and combustible material.

2. The entire length of furnace must be

supported when furnace is used in horizontal

position to ensure proper drainage.

A93304

Fig. 17—Crawlspace Horizontal Application

—15—

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IV. FILTER ARRANGEMENT

CAUTION: Never operate unit without a filter or with

blower access panel removed.

24¹⁄2-IN. WIDE

17¹⁄2-IN. WIDE

Factory-supplied washable framed filters are shipped in blower

compartment. Determine location for filter and relocate filter

retaining wire if necessary. See Table 2 to determine correct filter

size for desired filter location. Table 2 indicates filter size,

location, and quantity shipped with this furnace. See Fig. 2 for

location and size of bottom and side return-air openings.

CASINGS ONLY:

CUT AND FOLD

CASINGS ONLY:

INSTALL FIELD-SUPPLIED

FILTER FILLER STRIP

UNDER FILTER.

FACTORY-PROVIDED

FILTERS AS SHOWN

TO DESIRED SIZE.

3″

TABLE 2—FILTER INFORMATION

24 / ″

FURNACE

CASING

WIDTH (IN.)

FILTER SIZE (IN.)*

Side Return Bottom Return

FILTER TYPE

FRAMED

1″

17-1/2

(1) 16 X 25 X 1† (1) 16 X 25 X 1

(1) 16 X 25 X 1 (1) 20 X 25 X 1†

(2) 16 X 25 X 1† (1) 24 X 25 X 1

Cleanable

24-1/2

* Filters can be field modified by cutting frame as marked and folding to desired

size. Alternate sizes can be ordered from your distributor or dealer.

† Factory-provided with furnace.

CAUTION: Air delivery above 1800 CFM requires that

both sides, a combination of 1 side and bottom, or bottom

only of furnace be used for return air.

NOTE: Side return-air openings can ONLY be used in UPFLOW

configurations. Install filter(s) as shown in Fig. 18.

For bottom return-air applications, filter may need to be cut to fit

some furnace widths. Install filter as shown in Fig. 19.

NOTE: Remove and discard bottom closure panel when bottom

inlet is used.

WASHABLE

FILTER

V. BOTTOM CLOSURE PANEL

These furnaces are shipped with bottom closure panel installed in

bottom return-air opening. This panel MUST be in place when side

return air is used.

To remove bottom closure panel, perform following:

1. Tilt or raise furnace and remove 2 screws holding front

filler panel. (See Fig. 20.)

FILTER

RETAINER

FILTER

SUPPORT

2. Rotate front filler panel downward to release holding tabs.

3. Remove bottom closure panel.

A96030

4. Reinstall front filler panel and screws.

→ Fig. 19—Bottom Filter Arrangement

WASHABLE

FILTER

RETAINER

BOTTOM

CLOSURE

PANEL

FRONT FILLER

PANEL

A93045

A93047

Fig. 18—Filter Installed for Side Inlet

Fig. 20—Removing Bottom Closure Panel

—16—

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VI. GAS PIPING

GAS

Gas piping must be installed in accordance with national and local

codes. Refer to current edition of NFGC. Canadian installations

must be made in accordance with NSCNGPIC and all authorities

having jurisdiction. Gas supply line should be a separate line

running directly from meter to furnace, if possible. Refer to Table

3 for recommended gas pipe sizing. Risers must be used to connect

to furnace and to meter. Support all gas piping with appropriate

straps, hangers, etc. Use a minimum of 1 hanger every 6 ft. Joint

compound (pipe dope) should be applied sparingly and only to

male threads of joints. Pipe dope must be resistant to propane gas.

SUPPLY

MANUAL

SHUTOFF

VALVE

(REQUIRED)

SEDIMENT

TRAP

UNION

TABLE 3—MAXIMUM CAPACITY OF PIPE*

NOMINAL

LENGTH OF PIPE (FT)

IRON

PIPE

SIZE

(IN.)

INTERNAL

DIAMETER

(IN.)

1/2

3/4

0.622

0.824

1.049

1.380

1.610

175

360

120

250

465

950

A93324

200

375

770

170 151

320 285

660 580

Fig. 21—Typical Gas Pipe Arrangement

680

1-1/4

1-1/2

1400

→ ^{NOTE: The gas valve inlet press tap connection is suitable to use}

as test gage connection providing test pressure DOES NOT exceed

maximum 0.5 psig (14-in. wc) stated on gas valve. (See Fig. 48.)

Piping should be pressure tested in accordance with local and

national plumbing and gas codes before furnace has been attached.

In Canada, refer to current edition of NSCNGPIC. If pressure

exceeds 0.5 psig (14-in. wc), gas supply pipe must be disconnected

from furnace and capped before pressure test. If test pressure is

equal to or less than 0.5 psig (14-in. wc), turn off electric shutoff

switch located on gas valve before test. It is recommended that

ground joint union be loosened before pressure testing. After all

connections have been made, purge lines and check for leakage.

2100 1460 1180 990 900

* Cubic ft of gas per hr for gas pressures of 0.5 psig (14-in. wc) or less, and a

pressure drop of 0.5-in. wc (based on a 0.60 specific gravity gas). Ref: Table

10-2 NFPA 54-1996.

CAUTION: Connect gas pipe to furnace using a backup

wrench to avoid damaging gas controls.

→

WARNING: Gas valve shutoff switch MUST be facing

forward or tilted upward. Failure to follow this warning

could result in property damage or death.

ELECTRICAL CONNECTIONS

See Fig. 22 for field wiring diagram showing typical field 115-v

and 24-v wiring. Check all factory and field electrical connections

for tightness.

WARNING: Never purge a gas line into a combustion

chamber. Never use matches, candles, flame, or other

sources of ignition for purpose of checking leakage. Use

a soap-and-water solution to check for leakage. A failure

to follow this warning could result in fire, explosion,

personal injury, or death.

WARNING: Blower access panel door switch opens

115-v power to control center. No component operation

can occur. Do not bypass or close switch with panel

removed. Failure to follow this warning could result in

personal injury or death.

WARNING: Use proper length of pipe to avoid stress on

gas control manifold. Failure to follow this warning could

result in a gas leak resulting in fire, explosion, personal

injury, or death.

CAUTION: Furnace control must be grounded for

proper operation or control will lock out. Control is

grounded through green wire routed to gas valve and

burner box screw.

Install a sediment trap in riser leading to furnace. Trap can be

installed by connecting a tee to riser leading to furnace so

straight-through section of tee is vertical. Then connect a capped

nipple into lower end of tee. Capped nipple should extend below

level of gas controls. Place a ground joint union between gas

control manifold and manual gas shutoff valve. (See Fig. 21.)

I. 115-V WIRING

Before proceeding with electrical connections, make certain that

voltage, frequency, and phase correspond to that specified on unit

rating plate. Also, check to be sure that service provided by utility

is sufficient to handle load imposed by this equipment. Refer to

rating plate or Table 4 for equipment electrical specifications.

CAUTION: If a flexible connector is required or al-

lowed by authority having jurisdiction, black iron pipe

shall be installed at gas valve and extend a minimum of

2 in. outside furnace casing.

→ ^Makeall electrical connections in accordance with NEC

ANSI/NFPA 70-1996 and any local codes or ordinances that might

apply. For Canadian installations, all electrical connections must

be made in accordance with Canadian Electrical Code CSA C22.1

or subauthorities having jurisdiction.

An accessible manual shutoff valve MUST be installed upstream

of furnace gas controls and within 6 ft of furnace. A 1/8-in. NPT

plugged tapping, accessible for test gage connection, MUST be

installed immediately upstream of gas supply connection to

furnace and downstream of manual shutoff valve.

Use a separate, fused branch electrical circuit containing a properly

sized fuse or circuit breaker for this furnace. See Table 4 for wire

size and fuse specifications. A disconnecting means must be

located within sight from and readily accessible to furnace.

—17—

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FIELD 24-VOLT WIRING

FIELD 115-, 208/230-, 460-VOLT WIRING

FACTORY 24-VOLT WIRING

FACTORY 115-, 208/230-, 460-VOLT WIRING

NOTE 5

THERMOSTAT

TERMINALS

FIVE

WIRE

FIELD-SUPPLIED

FUSED DISCONNECT

THREE-WIRE

HEATING

ONLY

208/230- OR

460-VOLT

THREE

PHASE

W/W1

GND

115-VOLT

SINGLE

PHASE

NOTE

208/230-

VOLT

SINGLE

PHASE

115-VOLT

FUSED

AUXILIARY

J-BOX

GND

NOTE 1

DISCONNECT

SWITCH

CONDENSING

UNIT

Y/Y2

(WHEN REQUIRED)

TWO WIRE

NOTES:

24-VOLT

TERMINAL

BLOCK

FURNACE

CONTROL

CENTER

1. Connect Y or Y/Y2 terminal as shown for proper cooling operation.

2. Proper polarity must be maintained for 115-volt wiring.

3. Use W2 with 2-stage thermostat when zoning.

4. If any of the original wire, as supplied, must be replaced, use

same type or equivalent wire.

5. Some thermostats require a "C" terminal connection as shown.

A96338

→ Fig. 22—Heating and Cooling Application Wiring Diagram

ELECTRIC

DISCONNECT

SWITCH

FACTORY

INSTALLED

LOCATION

ALTERNATE

FIELD

COPPER

LOCATION

WIRE ONLY

ALUMINUM

WIRE

A93033

CAUTION: Do not connect aluminum wire between

disconnect switch and furnace. Use only copper wire.

NOTE: Proper polarity must be maintained for 115-v wiring. If

polarity is incorrect, control center fault code indicator light will

flash rapidly and furnace will NOT operate.

A93051

Fig. 23—Relocating J-Box

→

WARNING: The cabinet MUST have an uninterrupted

or unbroken ground according to NEC ANSI/NFPA

70-1996 and Canadian Electrical Code CSA C22.1 or

local codes to minimize personal injury if an electrical

fault should occur. This may consist of electrical wire or

conduit approved for electrical ground when installed in

accordance with existing electrical codes. Do not use gas

piping as an electrical ground. Failure to follow this

warning could result in electric shock, fire, or death.

CAUTION: If manual disconnect switch is to be

mounted on furnace, select a location where a drill or

fastener will not contact electrical or gas components.

II. 24-V WIRING

Make field 24-v thermostat connections at 24-v terminal block on

control center. Y wire from thermostat MUST be connected to Y

terminal on control center, as shown in Fig. 22, for proper cooling

operation. The 24-v terminal board is marked for easy connection

of field wiring. (See Fig. 24.) The 24-v circuit contains a 3-amp,

automotive-type fuse located on control center. (See Fig. 25.) Any

electrical shorts of 24-v wiring during installation, service, or

maintenance may cause fuse to blow. If fuse replacement is

required, use only a fuse of identical size (3 amp).

J-BOX RELOCATION

1. Remove 2 screws holding auxiliary J-box. (See Fig. 23.)

2. Rotate J-box 180° and attach box to right side, using holes

provided.

—18—

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)

S E U D H E W ( N

P S L G

O R

Y E

Y A

F F O - D E L

E R W B L O

B L K

W H

S T . T E P M C O

M Z

A T . H E R E M

B P

E A H T W L O

F L T

Y E

W H

B L K

W H

B L K

R E

B R

R E

B L K

W H

G R

B R

O R

Y E

W H

B L K

W H

G R

Y E

B R

O R

5 B L U

4 Y E

3 V I

R N 2 O

E D 1 R

B L U

C 2 E A

C 1 E A

W H

R E D

O R N O R N

V I O

Y E

V I O

Y E

B L

G R

B L

W H T

B L

W H T

B L

# 7 T E N O

N I D .

Y E

R E

—19—

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TABLE 4—ELECTRICAL DATA

OPERATING

VOLTAGE RANGE

VOLTS—

HERTZ—

PHASE

MAXIMUM

UNIT

AMPS

MINIMUM

WIRE

SIZE

UNIT

SIZE

UNIT

AMPACITY†

MAXIMUM WIRE

LENGTH (FT)‡

MAXIMUM FUSE OR

CKT BKR AMPS**

Maximum*

127

Minimum*

104

042040

042060

042080

060080

060100

060120

115—60—1

8.9

12.0

17.9

18.1

15.3

127

104

127

104

8.9

127

104

13.8

11.6

127

104

127

104

* Permissible limits of voltage range at which unit will operate satisfactorily.

† Unit ampacity = 125 percent of largest operating component’s full load amps plus 100 percent of all other potential operating components’ (EAC, humidifier, etc.) full load

amps.

‡ Length shown is as measured 1 way along wire path between unit and service panel for maximum 2 percent voltage drop.

** Time-delay fuse is recommended.

NOTE: Use AWG No. 18 color-coded copper thermostat wire for

lengths up to 100 ft. For wire lengths over 100 ft, use AWG No.

16 wire.

NOTE: For 2-speed applications, refer to Sequence of Operation

section.

(4.) Insert stripped end into factory-supplied white

leads’s butt connector and crimp to secure.

NOTE: If desired, cut butt connectors off factory leads and strip

insulation approximately 1/4 in and use field-supplied wire nuts to

connect.

III. ACCESSORIES

b. An alternate method to attach EAC lead to control center

is the following procedure:

1. Electronic Air Cleaner (EAC)

The control center EAC terminals are energized with 115v

(1.5-amp maximum) during blower operation.

a. Two extension leads are connected to the control center

EAC terminals to assist field installation of an EAC. (See

Fig. 25.) To use these leads, proceed with the following:

(1.) Remove 2 screws securing the control box to

furnace blower shelf.

(2.) Remove and discard 2 factory-supplied leads from

control center EAC terminals.

(1.) Strip EAC power lead insulation approximately 1/4

in.

(3.) Strip EAC power leads insulation approximately

1/8 in.

(2.) Insert stripped end into factory-supplied black

lead’s butt connector and crimp to secure.

NOTE: The control center EAC terminals are sized for 12 gage

maximum, solid or stranded wire.

(3.) Strip EAC neutral lead insulation approximately 1/4

in.

(4.) Route EAC leads through right-hand wire grommet.

HOT SURFACE

IGNITOR CONNECTOR

EAC-ELECTRONIC AIR

CLEANER TERMINALS

(115-VAC 1 AMP MAX)

115-V

CONNECTORS

PRESSURE SWITCH

CONNECTOR

HUM-HUMIDIFIER

TERMINAL

(24-VAC 0.5 AMP MAX)

MAIN BLOWER

CONTROL WIRE

CONNECTOR

24-V THERMOSTAT

TERMINALS

TRANSFORMER

24-V CONNECTORS

DEHUMIDIFIER (DH)

CONNECTOR

3-AMP FUSE

STATUS AND DIAGNOSTIC

LED LIGHTS

AIR CONDITIONING

(A/C) SETUP SWITCH

SETUP SWITCHES

(SW) AND BLOWER

OFF DELAY SETUP

SWITCHES

CONTINUOUS

FAN (CF) SETUP

SWITCHES

MODEL PLUG

COMMUNICATION

CONNECTOR

A93062

Fig. 25—Control Center

—20—

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connected to the venting system. Turn on any exhaust fans,

such as range hoods and bathroom exhausts, so they shall

operate at maximum speed. Do not operate a summer

exhaust fan. Close fireplace dampers.

4. Follow the lighting instructions. Place the appliance being

inspected in operation. Adjust thermostat so appliance shall

operate continuously.

EAC1

5. Test for draft hood equipped appliance spillage at the draft

hood relief opening after 5 minutes of main burner opera-

tion. Use the flame of a match or candle.

6. After it has been determined that each appliance connected

to the venting system properly vents when tested as outlined

above, return doors, windows, exhaust fans, fireplace damp-

ers, and any other gas-burning appliance to their previous

conditions of use.

EAC2

Fig. 26—EAC Terminals on Control Center

A93053

7. If improper venting is observed during any of above tests,

the venting system must be corrected.

(5.) Insert EAC stripped leads into control center EAC

terminals by depressing terminal’s arm with a

screwdriver or finger. (See Fig. 26.)

Vent system or vent connectors may need to be resized. For any

other appliances when resizing vent systems or vent connectors,

system or connector must be sized to approach minimum size as

determined using appropriate table found in the NFGC or NSC-

NGPIC.

(6.) Reinstall control box to furnace blower shelf using

2 screws removed earlier.

2. Humidifier (HUM)

II. COMBUSTION-AIR AND VENT PIPING

A. General

Screw terminals (HUM and C^OM) are provided for 24-v

humidifier connection. (See Fig. 24.) HUM terminal is

energized with 24v (0.5-amp maximum) after inducer

motor prepurge period.

Combustion-air and vent pipe fittings must conform to American

National Standards Institute (ANSI) standards and American

Society for Testing and Materials (ASTM) standards D1785

(schedule-40 PVC), D2665 (PVC-DWV), D2241 (SDR-21 and

SDR-26 PVC), D2661 (ABS-DWV), F628 (schedule-40 ABS), or

F891 (PVC-DWV cellular core). Pipe cement and primer must

conform to ASTM standards D2564 (PVC) or D2235 (ABS). See

Table 6 for maximum pipe lengths and Fig. 31, 32, 33, 34, and 35

for exterior piping arrangements.

NOTE: A field-supplied, 115-v controlled relay connected to

EAC terminals may be added if humidifier operation is desired

during blower operation.

3. Dehumidification (DH)

A 1/4-in. male quick-connect terminal is provided on

control center to attach a normally open (N/O) humidistat

contact when dehumidification is desired. (See Fig. 25.)

Connect humidistat to thermostat R terminal and DH

terminal on control center. A 15 percent reduction of

cooling airflow or constant fan airflow will occur when DH

terminal is energized and a single- or 2-speed "call for

cooling" is received.

In Canada, construct all combustion-air and vent pipes for this unit

of CSA or ULC certified schedule-40 PVC, PVC-DWV or

ABS-DWV pipe and pipe cement. SDR pipe is NOT approved in

Canada.

NOTE: Furnace combustion-air and vent pipe connections are

sized for 2-in. pipe. Any pipe size change should be made outside

furnace casing in vertical pipe. (See Fig. 27.) This allows proper

drainage of vent condensate.

DIRECT VENTING

The 355MAV Furnaces require a dedicated (one 355MAV furnace

only) direct-vent system. In a direct-vent system, all air for

combustion is taken directly from outside atmosphere, and all flue

products are discharged to outside atmosphere.

Combustion-air and vent pipes must terminate together in same

atmosphere pressure zone, either through roof or sidewall (roof

termination preferred), using accessory termination kit. See Table

5 for required clearances.

I. REMOVAL OF EXISTING FURNACES FROM

COMMON VENT SYSTEMS

Furnace combustion-air and vent pipe connections must be at-

tached as shown in Fig. 28. Combustion-air intake plug fitting and

inducer housing alternate vent cap may need to be relocated in

some applications.

If furnace being replaced was connected to a common vent system

with other appliances, the following steps shall be followed with

each appliance connected to the venting system placed in opera-

tion, while any other appliances connected to the venting system

are not in operation:

CAUTION: When combustion-air pipe is installed

above a suspended ceiling, pipe must be insulated with

3/8-in. thick Armaflex-type insulation. Combustion-air

pipe should also be insulated when it passes through a

warm, humid space.

1. Seal any unused openings in the venting system.

2. Inspect the venting system for proper size and horizontal

pitch as required in the National Fuel Gas Code, ANSI

Z223.1 or the CAN/CGA B149 Installation Codes and these

instructions. Determine that there is no blockage or restric-

tion, leakage, corrosion, and other deficiencies which could

cause an unsafe condition.

CAUTION: When vent pipe is exposed to temperatures

below freezing, such as when it passes through an

unheated space or when a chimney is used as a raceway,

pipe must be insulated as shown in Table 7 with

Armaflex-type insulation.

3. If practical, close all building doors and windows and all

doors between the space in which the appliance(s) con-

nected to the venting system are located and other spaces of

the building. Turn on clothes dryers and any appliance not

—21—

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TABLE 5—COMBUSTION-AIR AND VENT PIPE

TERMINATION CLEARANCES

NOTE: Select 1 vent pipe connection and NOTE: Select 1 vent pipe connection and

1 combustion-air pipe connection.

AIR

FLOW

CLEARANCE (FT)

LOCATION

COMBUSTION-

AIR

COMBUSTION-

AIR

U.S.A.

Canada

VENT

Above grade level or above antici-

pated snow depth

1†

VENT

Dryer vent

VENT

From plumbing vent stack

From any mechanical fresh air intake

For furnaces with an input capacity

less than 100,000 Btuh—from any

non-mechanical air supply (windows

or doors which can be opened) or

combustion-air opening

COMBUSTION-

AIR

COMBUSTION-

AIR

FLOW

UPFLOW

DOWNFLOW

For furnaces with an input capacity

greater than 100,000 Btuh—from any

non-mechanical air supply (windows

or doors which can be opened) or

combustion-air opening

COMBUSTION-

AIR

COMBUSTION-

AIR

VENT

From service regulator vent, electric

and gas meters, and relief equipment

6‡

Above grade when adjacent to public

walkway

AIR

FLOW

AIR

FLOW

* Horizontal distance.

† 18 in. above roof surface in Canada.

‡ 36 in. to electric meter in Canada only.

NOTES:

1. If installing 2 adjacent 355MAV Furnaces, refer to Multiventing and Vent

Terminations section for proper vent configurations.

2. When locating combustion-air and vent terminations, consideration must be

given to prevailing winds, location, and other conditions which may cause

recirculation of the appliance’s own flue products or the flue products of

adjacent vents. Recirculation can cause poor combustion, inlet condensate

problems, and accelerated corrosion of heat exchangers.

HORIZONTAL-LEFT DISCHARGE

HORIZONTAL-RIGHT DISCHARGE

A96187

Fig. 28—Combustion-Air and Vent Pipe Connections

WARNING: Solvent cements are combustible. Keep

away from heat, sparks, and open flame. Use only in well

ventilated areas. Avoid breathing in vapor or allowing

contact with skin or eyes. Failure to follow this warning

could result in fire, property damage, personal injury, or

death.

FURNACE

NOT IN

HORIZONTAL

SECTION

PIPE DIAMETER

TRANSITION IN

WARNING: All combustion-air and vent pipes must be

airtight and watertight. Pipes must also terminate exactly

as shown in Fig. 31, 32, 33, 34, or 35. Failure to follow

this warning could result in property damage, personal

injury, or death.

VERTICAL SECTION

A93034

Fig. 27—Combustion-Air and Vent Pipe Diameter

Transition Location and Elbow Configuration

NOTE: The minimum combustion-air and vent pipe length (each)

for these furnaces is 5 ft. Short pipe lengths (5-8 ft) may discharge

water droplets. These droplets may be undesirable, and a 12-in.

minimum offset pipe section is recommended, as shown in Fig. 29,

to reduce excessive droplets from exiting vent pipe outlet.

CAUTION: Combustion air must not be taken from

inside structure because that air is frequently contami-

nated by halogens, which include fluorides, chlorides,

bromides, and iodides. These elements are found in

aerosols, detergents, bleaches, cleaning solvents, salts, air

fresheners, adhesives, paint, and other household prod-

ucts. Locate combustion-air inlet as far as possible from

swimming pool and swimming pool pump house.

B. Combustion-Air and Vent Pipe Diameter

Determine combustion-air and vent pipe diameter.

1. Using Table 6, individually determine the combustion-air

and vent pipe diameters. Pick the larger of these 2 pipe

diameters and use this diameter for both combustion-air and

vent pipes.

Excessive exposure to contaminated combustion air will

result in safety and performance related problems.

2. When installing vent systems of short pipe length, use the

smallest allowable pipe diameter. Do not use pipe size

greater than required or incomplete combustion, flame

disturbance, or flame sense lockout may occur.

NOTE: Do not count elbows or pipe sections in terminations or

within furnace. See shaded areas in Fig. 31, 32, 33, 34, and 35.

—22—

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b. Reposition combustion-air intake housing plug fitting in

appropriate unused intake housing connection.

EXAMPLE:

An 042080 size furnace located in Indianapolis, elevation

650 ft above sea level, could be installed in an application

requiring 3 elbows and 17 ft of vent pipe, along with 5

elbows and 16 ft of combustion-air pipe. Table 6 indicates

this application would allow a 1-1/2-in. diameter vent pipe,

but require a 2-in. diameter combustion air pipe (1-1/2-in.

pipe is good for 20 ft with 3 elbows, but only 10 ft with 5

elbows). Therefore, 2-in. diameter pipe must be used for

both vent and combustion-air pipes since larger required

diameter must always be used for both pipes. If same

installation were in Albuquerque, elevation 5250 ft above

sea level, installation would require 2-in. vent pipe and

combustion-air pipe. At 5001- to 6000-ft elevation, 1-1/2-

in. pipe is not allowed with 5 elbows, but 2-in. pipe is good

for 68 ft with 5 elbows.

c. Insert perforated disk assembly (factory supplied) in

intake housing where combustion-air intake pipe will be

connected.

d. Install pipe support (factory-supplied in loose parts bag)

into selected furnace casing combustion-air pipe hole.

Pipe support should be positioned to bottom of casing

hole.

e. Insert 2-in. diameter pipe into intake housing.

NOTE: A 2-in. diameter pipe must be used within the furnace

casing. Make all pipe diameter transitions outside furnace casing.

f. Drill a 1/8-in. hole in 2-in. combustion-air pipe using

hole in intake housing as a guide.

g. Install a field-supplied No. 6 or No. 8 sheet metal screw

into combustion-air pipe.

C. Combustion-Air and Vent Pipe Attachment

NOTE: All pipe joints must be watertight except attachment of

combustion-air pipe to inlet housing connection since it may be

necessary to remove pipe for servicing.

NOTE: DO NOT OVERTIGHTEN SCREW. Breakage to intake

housing or fitting may cause air leakage to occur.

NOTE: Do not attach combustion-air intake pipe permanently to

combustion-air intake housing since it may be necessary to remove

pipe for service of ignitor or flame sensor.

1. Attach combustion-air pipe as follows:

a. Determine location of combustion-air intake pipe con-

nection to combustion-air intake housing as shown in

Fig. 28 for application.

12″ MIN

VENT PIPE

COMBUSTION-AIR PIPE

HORIZONTAL TO ROOF

HORIZONTAL TO SIDEWALL

COMBUSTION-AIR PIPE

VENT PIPE

COMBUSTION-AIR PIPE

12″ MIN

VENT PIPE

VERTICAL TO ROOF

VERTICAL TO SIDEWALL

NOTE: A 12 In. minimum offset pipe section is recommended with

short (5 to 8 ft) vent systems. This recommendation is to reduce

excessive condensate droplets from exiting the vent pipe.

A96230

Fig. 29—Short Vent (5 to 8 Ft) System

—23—

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TABLE 6—MAXIMUM ALLOWABLE PIPE LENGTH (FT)

NUMBER OF 90° ELBOWS

UNIT

SIZE

TERMINATION

TYPE

PIPE DIAMETER

(IN.)*

ALTITUDE

1-1/2

2 Pipe or 2-In.

Concentric

042040

042060

1-1/2

2 Pipe or 2-In.

Concentric

1-1/2

042080

060080

2 Pipe or 2-In.

Concentric

0 to 2000

2 Pipe or 2-In.

Concentric

060100

2-1/2

2 Pipe or 3-In.

Concentric

060120

3†

NUMBER OF 90° ELBOWS

UNIT

SIZE

TERMINATION

TYPE

PIPE DIAMETER

(IN.)*

ALTITUDE

1-1/2

2 Pipe or 2-In.

Concentric

042040

042060

1-1/2

2 Pipe or 2-In.

Concentric

1-1/2

042080

060080

2 Pipe or 2-In.

Concentric

2001 to 3000

2 Pipe or 2-In.

Concentric

060100

060120

2-1/2

2 Pipe or 3-In.

Concentric

3†

NUMBER OF 90° ELBOWS

UNIT

SIZE

TERMINATION

TYPE

PIPE DIAMETER

(IN.)*

ALTITUDE

1-1/2

2 Pipe or 2-In.

Concentric

042040

042060

1-1/2

2 Pipe or 2-In.

Concentric

1-1/2

042080

060080

2 Pipe or 2-In.

Concentric

3001 to 4000

2 Pipe or 2-In.

Concentric

060100

060120

2-1/2

2 Pipe or 3-In.

Concentric

3†

NUMBER OF 90° ELBOWS

UNIT

SIZE

TERMINATION

TYPE

PIPE DIAMETER

(IN.)*

ALTITUDE

1-1/2

2 Pipe or 2-In.

Concentric

042040

042060

1-1/2

2 Pipe or 2-In.

Concentric

1-1/2

042080

060080

2 Pipe or 2-In.

Concentric

4001 to 5000‡

2 Pipe or 2-In.

Concentric

060100

060120

2-1/2

2 Pipe or 3-In.

Concentric

3†

NUMBER OF 90° ELBOWS

UNIT

SIZE

TERMINATION

TYPE

PIPE DIAMETER

(IN.)*

ALTITUDE

1-1/2

2 Pipe or 2-In.

Concentric

042040

042060

1-1/2

2 Pipe or 2-In.

Concentric

1-1/2

042080

060080

2 Pipe or 2-In.

Concentric

5001 to 6000‡

2 Pipe or 2-In.

Concentric

060100

060120

2-1/2

2 Pipe or 3-In.

Concentric

3†

See notes on next page.

—24—

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TABLE 6—MAXIMUM ALLOWABLE PIPE LENGTH (FT) Continued

NUMBER OF 90° ELBOWS

UNIT

SIZE

TERMINATION

TYPE

PIPE DIAMETER

(IN.)*

ALTITUDE

1-1/2

2 Pipe or 2-In.

Concentric

042040

042060

1-1/2

2 Pipe or 2-In.

Concentric

1-1/2

042080

060080

2 Pipe or 2-In.

Concentric

6001 to 7000‡

2 Pipe or 2-In.

Concentric

060100

060120

2-1/2

2 Pipe or 3-In.

Concentric

3†

NUMBER OF 90° ELBOWS

UNIT

SIZE

TERMINATION

TYPE

PIPE DIAMETER

(IN.)*

ALTITUDE

1-1/2

2 Pipe or 2-In.

Concentric

042040

042060

1-1/2

2 Pipe or 2-In.

Concentric

1-1/2

042080

060080

2 Pipe or 2-In.

Concentric

7001 to 8000‡

2 Pipe or 2-In.

Concentric

060100

060120

2-1/2

2 Pipe or 3-In.

Concentric

3†

NUMBER OF 90° ELBOWS

UNIT

SIZE

TERMINATION

TYPE

PIPE DIAMETER

(IN.)*

ALTITUDE

1-1/2

2 Pipe or 2-In.

Concentric

042040

042060

1-1/2

2 Pipe or 2-In.

Concentric

1-1/2

042080

060080

2 Pipe or 2-In.

Concentric

8001 to 9000‡

2 Pipe or 2-In.

Concentric

060100

060120

2-1/2

2 Pipe or 3-In.

Concentric

3†

NUMBER OF 90° ELBOWS

UNIT

SIZE

TERMINATION

TYPE

PIPE DIAMETER

(IN.)*

ALTITUDE

1-1/2

2 Pipe or 2-In.

Concentric

042040

042060

1-1/2

2 Pipe or 2-In.

Concentric

1-1/2

042080

060080

2 Pipe or 2-In.

Concentric

9001 to 10000‡

2 Pipe or 2-In.

Concentric

060100

060120

2-1/2

2 Pipe or 3-In.

Concentric

3†

* Disk usage—Unless otherwise stated, use perforated disk assembly (factory-supplied in loose parts bag).

† Wide radius elbow.

‡ Vent sizing for Canadian installations over 4500 ft (1370m) above sea level are subject to acceptance by the local authorities having jurisdiction.

NA—Not Allowed; pressure switch will not make.

NOTES:

1. Do not use pipe size greater than those specified in table or incomplete combustion, flame disturbance, or flame sense lockout may occur.

2. Size both the combustion-air and vent pipe independently, then use the larger diameter for both pipes.

3. Assume two 45° elbows equal one 90° elbow. Long radius elbows are desirable and may be required in some cases.

4. Elbows and pipe sections within the furnace casing and at the vent termination should not be included in vent length or elbow count.

5. The minimum pipe length is 5 ft for all applications.

—25—

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COMBUSTION-AIR INTAKE HOUSING PLUG

FITTING

WARNING: Vent pipe must be installed and fully

seated against inducer housing. Clamp must be tightened

to prevent any condensate leakage. Failure to follow this

warning could result in electrical shock, fire, personal

injury, or death.

The combustion-air intake plug fitting must be installed in

unused combustion-air intake housing. This fitting must be

attached by using RTV sealant, or by drilling a 1/8-in. hole

in fitting, using hole in intake housing as a guide. Install a

field-supplied No. 6 or No. 8 sheet metal screw.

NOTE: A 2-in. diameter pipe must be used within the furnace

casing. Make all pipe diameter transitions outside furnace casing.

NOTE: DO NOT OVERTIGHTEN SCREW. Breakage to intake

housing or fitting may cause air leakage to occur.

3. Working from furnace to outside, cut pipe to required

length(s).

A plugged drain connection has been provided on this

fitting for use when moisture is found in combustion-air

intake pipe and combustion box.

4. Deburr inside and outside of pipe.

5. Chamfer outside edge of pipe for better distribution of

primer and cement.

NOTE: Moisture in combustion-air intake may be result of

improper termination. Ensure combustion-air intake pipe is similar

to that shown in Fig. 31, 32, 33, 34, or 35 so it will not be

susceptible to areas where light snow or other sources of moisture

could be pulled in.

6. Clean and dry all surfaces to be joined.

7. Check dry fit of pipe and mark insertion depth on pipe.

NOTE: It is recommended that all pipes be cut, prepared, and

preassembled before permanently cementing any joint.

If use of this drain connection is desired, drill out fitting’s

tap plug with a 3/16-in. drill and connect a field-supplied

3/8-in. tube. This tube should be routed to open condensate

drain for furnace and A/C (if used), and should be trapped.

(See Fig. 30.)

8. After pipes have been cut and preassembled, apply gener-

ous layer of cement primer to pipe fitting socket and end of

pipe to insertion mark. Quickly apply approved cement to

end of pipe and fitting socket (over primer). Apply cement

in a light, uniform coat on inside of socket to prevent

buildup of excess cement. Apply second coat.

COMBUSTION – AIR

INTAKE HOUSING

9. While cement is still wet, twist pipe into socket with 1/4

turn. Be sure pipe is fully inserted into fitting socket.

3/8" ID TUBE

BURNER

BOX

10. Wipe excess cement from joint. A continuous bead of

cement will be visible around perimeter of a properly made

joint.

11. Handle pipe joints carefully until cement sets.

3/16"

12. Support combustion-air and vent piping a minimum of

every 5 ft (3 ft for SDR-21 or -26 PVC) using perforated

metal hanging strap.

DRILL

COMBUSTION –

AIR PIPE

4″

MIN

13. Slope combustion-air and vent pipes toward furnace a

minimum of 1/4 in. per linear ft with no sags between

hangers.

TRAP

TO OPEN

DRAIN

14. Use appropriate methods to seal openings where vent and

combustion-air pipes pass through roof or sidewall.

A93035

Fig. 30—Intake Housing Plug Fitting Drain

III. CONCENTRIC VENT AND COMBUSTION-AIR

TERMINATION KIT INSTALLATION

NOTE: If these instructions differ from those packaged with

termination kit, follow kit instructions.

2. Attach vent pipe as follows:

a. Determine location of vent pipe connection to inducer

housing as shown in Fig. 28 for application.

Combustion-air and vent pipes must terminate outside structure. A

factory accessory termination kit must be installed in 1 of the

installations shown in Fig. 31, 32, 33, 34, or 35. Four termination

kits are available.

b. Reposition neoprene inducer housing outlet cap and

clamp to appropriate unused inducer housing connec-

tion. Tighten clamp.

1. The 2-in. termination bracket kit is for 1-in., 1-1/2 in., and

2-in. diameter 2-pipe termination systems.

WARNING: Inducer housing outlet cap must be in-

stalled and fully seated against inducer housing. Clamp

must be tightened to prevent any condensate leakage.

Failure to follow this warning could result in electrical

shock, fire, personal injury, or death.

2. The 3-in. termination bracket kit is for 2-1/2 in. and 3-in.

diameter 2-pipe termination systems.

3. The 2-in. concentric vent/air termination kit is for 1-in.,

1-1/2 in., 2-in., and 2-1/2 in. diameter pipe systems when

single penetration of wall or roof is desired.

4. The 3-in. concentric vent/air termination kit is for 2-1/2 in.

and 3-in. diameter pipe systems when single penetration of

wall or roof is desired.

c. Install pipe support (factory-supplied in loose parts bag)

into selected furnace casing vent pipe hole. Pipe support

should be positioned to bottom of casing hole.

NOTE: Shaded parts in Fig. 31, 32, 33, 34, and 35 are considered

to be terminations. These components should NOT be counted

when determining pipe diameter. Roof termination is preferred

since it is less susceptible to damage, has reduced chances to intake

d. Insert 2-in. diameter pipe into inducer housing through

neoprene coupling and clamp in inducer housing.

Tighten clamp.

—26—

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ROOF

18″ MAXIMUM

BRACKET

COUPLING

COMBUSTION

AIR

VERTICAL SEPARATION

BETWEEN COMBUSTION

AIR AND VENT

VENT

/ ″ FOR 3″ KIT

/ ″ FOR 2″ KIT

MAINTAIN 12 IN. MINIMUM

CLEARANCE ABOVE HIGHEST

ANTICIPATED SNOW LEVEL.

MAXIMUM OF 24 IN. ABOVE ROOF.

A87224

Fig. 31—Roof Termination (Preferred)

OVERHANG OR ROOF

12″ MINIMUM

1″ MAXIMUM

VENT

COMBUSTION-AIR

VENT

COMBUSTION

AIR

MAINTAIN 12 IN.

CLEARANCE

(18 IN. FOR CANADA)

MINIMUM CLEARANCE

ABOVE HIGHEST

ANTICIPATED SNOW

LEVEL OR GRADE,

WHICHEVER IS

GREATER.

ANTICIPATED SNOW

LEVEL. MAXIMUM OF

24 IN. ABOVE ROOF.

A93055

A93054

Fig. 33—Concentric Vent and Combustion-Air Side

Termination

Fig. 32—Concentric Vent and Combustion-Air Roof

Termination (Preferred)

OVERHANG OR ROOF

12″ MINIMUM

VENT

90°

BRACKET

COUPLING

12 IN. SEPARATION

BETWEEN BOTTOM OF

COMBUSTION AIR AND

BOTTOM OF VENT

BETWEEN BOTTOM OF

COMBUSTION AIR AND

BOTTOM OF VENT

MAINTAIN 12 IN.

CLEARANCE

MAINTAIN 12 IN.

CLEARANCE

ABOVE HIGHEST

ANTICIPATED SNOW

ABOVE HIGHEST

ANTICIPATED SNOW

LEVEL OR GRADE,

WHICHEVER IS

GREATER.

COMBUSTION-AIR

(ELBOW PARALLEL

TO WALL)

COMBUSTION-AIR

WHICHEVER IS

GREATER.

A87225

A87226

Fig. 34—Sidewall Termination of 12 in. or More

Fig. 35—Sidewall Termination of Less than 12 in.

—27—

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TABLE 7—MAXIMUM ALLOWABLE EXPOSED VENT PIPE LENGTH (FT) WITH INSULATION IN WINTER DESIGN

TEMPERATURE AMBIENT*

WINTER DESIGN

TEMPERATURE

(°F)

MAXIMUM PIPE

DIAMETER

(IN.)

INSULATION THICKNESS (IN.)†

UNIT

SIZE

3/8

1/2

3/4

042040

042060

-20

042080

060080

-20

2-1/2

060100

060120

-20

* Pipe length (ft) specified for maximum pipe lengths located in unconditioned spaces. Pipes located in unconditioned space cannot exceed total allowable pipe length as

specified in Table 6.

† Insulation thickness based on R value of 3.5 per in.

contaminants, and has less visible vent vapors. (See Fig. 31 or 32.)

Sidewall termination may require sealing or shielding of building

surfaces with a corrosive resistance material due to corrosive

combustion products of vent system.

Roof terminations—Loosely install pipe coupling on prop-

erly cut vent pipe. Coupling must be positioned so bracket

will mount as shown in Fig. 31.

For applications using combustion-air pipe option indicated

by dashed lines in Fig. 31, install 90° street elbow into 90°

elbow, making U-fitting. A 180° U-fitting may be used.

A. Extended Exposed Sidewall Pipes

Sidewall combustion-air and vent pipe terminations may be

extended beyond area shown in Fig. 34 or 35 in outside ambient by

insulating pipes as indicated in Table 7.

Sidewall terminations—Install bracket as shown in Fig. 34

or 35.

1. Determine combustion-air and vent pipe diameters, as

stated above, using total pipe length and number of elbows.

For applications using vent pipe option indicated by dashed

lines in Fig. 34, rotate vent elbow 90° from position shown

in Fig. 34.

2. Using winter design temperature (used in load calculations),

find appropriate temperature for your application and fur-

nace model.

4. Disassemble loose pipe fittings. Clean and cement using

same procedures as used for system piping.

3. Determine required insulation thickness for exposed pipe

lengths.

5. Check required dimensions as shown in Fig. 31, 34, or 35.

C. Concentric Vent/Air Termination Kit

1. Determine location for termination.

NOTE: Pipe length (ft) specified for maximum pipe lengths

located in unconditioned spaces cannot exceed total allowable pipe

length as specified in Table 6.

Consideration of the following should be made when

determining an appropriate location for termination kit.

B. Two-Pipe Termination Kit

1. Determine location for termination.

a. Comply with all clearance requirements as stated in

Table 5.

Consideration of the following should be made when

determining an appropriate location for termination kit.

b. Termination kit should be positioned where vent vapors

will not damage plants/shrubs or air conditioning equip-

ment.

a. Comply with all clearance requirements as stated in

Table 5.

b. Termination kit should be positioned where vent vapors

will not damage plants/shrubs or air conditioning equip-

ment.

c. Termination kit should be positioned so it will not be

affected by wind eddy (such as inside building corners)

or accumulation of airborne leaves or light snow, or

allow recirculation of flue gases.

c. Termination kit should be positioned so it will not be

affected by wind eddy (such as inside building corners)

or accumulation of airborne leaves or light snow, or

allow recirculation of flue gases.

d. Termination kit should be positioned where it will not be

damaged by or subjected to foreign objects, such as

stones, balls, etc.

d. Termination kit should be positioned where it will not be

damaged by or subjected to foreign objects, such as

stones, balls, etc.

e. Termination kit should be positioned where vent vapors

are not objectionable.

2. Cut one 4-in. diameter hole for 2-in. kit, or one 5-in.

diameter hole for 3-in. kit.

e. Termination kit should be positioned where vent vapors

are not objectionable.

3. Loosely assemble concentric vent/air termination compo-

nents together using instructions in kit.

2. Cut 2 holes, 1 for each pipe, of appropriate size for pipe size

being used.

3. Loosely install elbow in bracket and place assembly on

combustion-air pipe.

4. Slide assembled kit with rain shield REMOVED through

hole.

—28—

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NOTE: Do not allow insulation or other materials to accumulate

inside of pipe assembly when installing it through hole.

Roof terminations—Locate assembly through roof to ap-

propriate height as shown in Fig. 32.

Sidewall terminations—Locate assembly through sidewall

with rain shield positioned no more than 1-in. from wall as

shown in Fig. 33.

5. Disassemble loose pipe fittings. Clean and cement using

same procedures as used for system piping.

32°F MINIMUM INSTALLED

AMBIENT OR FREEZE

PROTECTION REQUIRED

6. Check required dimensions as shown in Fig. 32 or 33.

IV. MULTIVENTING AND VENT TERMINATIONS

When 2 or more 355MAV Furnaces are vented near each other,

each furnace must be individually vented. NEVER common vent

or breach vent 355MAV furnaces. When 2 or more 355MAV

furnaces are vented near each other, 2 vent terminations may be

installed as shown in Fig. 36, 37, 38, 39, or 40, but next vent

termination must be at least 36 in. away from first 2 terminations.

It is important that vent terminations be made as shown to avoid

recirculation of flue gases. Dimension "A" in Fig. 36, 37, 38, 39,

and 40 represents distance between pipes or rain shields, as

touching or 2-in. maximum separation.

A93058

CAUTION: Unit must not be installed, operated, and

then turned and left off in an unoccupied structure during

cold weather when temperature drops to 32°F or below

unless drain trap and drain line have adequate freeze

protection. See Service and Maintenance Procedures for

winterizing procedure.

CONDENSATE DRAIN

I. GENERAL

Condensate trap is shipped installed in the blower shelf and factory

connected for UPFLOW applications. Condensate trap must be

RELOCATED for use in DOWNFLOW and HORIZONTAL

applications.

Outdoor draining of the furnace is permissible if allowed by local

codes. Caution should be taken when freezing ambient may freeze

drain pipe and prohibit draining.

Condensate trap MUST be used for all applications.

An external trap is not required when connecting the field drain to

this condensate trap.

WARNING: Caution should be taken to prevent drain-

ing where slippery conditions may cause personal inju-

ries. Excessive condensate draining may cause saturated

soil conditions which may result in damage to plants.

The field drain connection (condensate trap or drain tube coupling)

is sized for 1/2-in. CPVC, 1/2-in. PVC, or 5/8-in. ID tube

connection.

Drain pipe and fittings must conform to ANSI standards and

ASTM D1785 or D2846. CPVC or PVC cement and primer must

conform to ASTM D2564 or F493. In Canada, use CSA or ULC

certified schedule 40 CPVC or PVC drain pipe, fittings, and

cement.

III. CONDENSATE DRAIN PROTECTION

Freezing condensate left in condensate trap and drain line may

cause cracks, and possible water damage may occur. If freeze

protection is required, use condensate freeze protection accessory

or equivalent 3 to 6 watt per ft at 120v and 40°F self-regulating,

shielded, and waterproof heat tape. See Installation Instructions

supplied with accessory or heat tape manufacturer’s recommenda-

tions.

When a condensate pump is required, select a pump which is

approved for condensing furnace applications. To avoid conden-

sate spillage, select a pump with an overflow switch.

Furnace condensate is mildly acidic, typically in the pH range of

3.2 to 4.5. Due to corrosive nature of this condensate, a condensate

pH neutralizing filter may be desired. Check with local authorities

to determine if a pH neutralizer is required.

1. Fold heat tape in half and wrap on itself 3 times.

2. Locate heat tape between sides of condensate trap back.

(See Fig. 42.)

II. APPLICATION

3. Use wire ties to secure heat tape in place. Wire ties can be

positioned in notches of condensate trap sides. (See Fig.

42.)

The furnace, A/C, and humidifier drains may be combined and

drained together. The A/C drain must have an external, field-

supplied trap prior to the furnace drain connection. All drain

connections (furnace, A/C, or humidifier) must be terminated into

an open or vented drain as close to the respective equipment as

possible to prevent siphoning of the equipment’s drain.

4. Wrap field drain pipe with remaining heat tape, approxi-

mately 1 wrap per ft.

5. When using field-supplied heat tape, follow heat tape

manufacturer’s instructions for all other installation guide-

lines.

See Fig. 41 for example of possible field drain attachment using

1/2-in. CPVC or PVC tee for vent and A/C or humidifier drain

connection.

—29—

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A96128

Fig. 36—Rooftop Termination (Dimension "A" is Touching or 2-In. Maximum Separation)

1″ MAXIMUM

(TYP)

VENT

COMBUSTION AIR

VENT

COMBUSTION

AIR

VENT

A93056

A93057

Fig. 37—Concentric Vent and Combustion-Air Roof

Termination (Dimension "A" is Touching or

2-In. Maximum Separation)

Fig. 38—Concentric Vent and Combustion-Air Side

Termination (Dimension "A" is Touching or

2-In. Maximum Separation)

VENT

COMBUSTION AIR

A96129

A96130

Fig. 39—Sidewall Termination of 12 in. or Less

(Dimension "A" is Touching or 2-In.

Maximum Separation)

Fig. 40—Sidewall Termination of More Than 12 in.

(Dimension "A" is Touching or 2-In.

Maximum Separation)

—30—

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I. SELF-TEST MODE

The control center goes through a brief self-test whenever 115-v or

24-v power is interrupted. The self-test takes approximately 2 sec

to complete. After power is restored, red (microprocessor) LED

briefly comes on. Then green LED comes on for 1 sec, followed by

1 sec where both yellow and green LEDs are on. During this time,

the microprocessor is checking itself.

II. HEATING MODE

When thermostat calls for heat, R-W/W1 circuit closes.

OPEN STAND

PIPE FOR

A/C OR

1. Prepurge period—The inducer motor is turned on and

slowly comes up to speed. When low-pressure switch

closes, inducer motor RPM is noted by microprocessor, and

a 25 sec prepurge period begins. The RPM is used to

evaluate vent system resistance. This evaluation is then

used to determine required RPM necessary to operate

inducer in low-heat mode.

HUMIDIFIER

DRAIN

TEE

NOTE: The heat cycle can start in either high or low heat. If a

high-heat cycle is initiated, the inducer continues increasing its

speed after low-pressure switch closes. When high-pressure switch

closes, inducer motor RPM is noted by microprocessor before the

25 sec prepurge period begins. The RPM is used to evaluate vent

system resistance. This evaluation is then used to determine

required RPM necessary to operate inducer in high-heat mode.

TO OPEN

DRAIN

2. Humidifier (HUM)—The HUM terminal is energized after

the inducer prepurge period is completed.

A94054

3. Ignitor warm up—At end of prepurge period, the hot

surface ignitor (HSI) is energized for a 17-sec HSI warm-up

period.

Fig. 41—Example of Field Drain Attachment

4. Ignition sequence—After HSI ignitor warm-up period is

completed, the gas valve opens, permitting gas flow to

burners where it is ignited. After 5 sec, the HSI is

de-energized, and a 2-sec flame-sensing period begins.

CONDENSATE TRAP

NOTE: The initial heat mode after 115-v or 24-v power interrup-

tion will be LOW HEAT. Low heat remains energized for 16

minutes before high heat is initiated, providing thermostat is still

calling for heat.

After initial cycle, the microprocessor evaluates the length of low-

and high-heat operating times and calculates optimum length of

low and high heat for next heat cycle. This accommodates the heat

load requirement seen as a result of thermostat operating time.

WIRE TIE(S)

5. Flame sensing—When burner flame is sensed, the control

center holds gas valve open and begins blower on delay

period.

HEAT TAPE

(3 WRAPS MINIMUM)

NOTE: Ignition sequence repeats 3 additional times before a

lockout occurs. Lockout automatically resets after 3 hr, or can be

manually reset by turning 115-v or 24-v power off (not at

thermostat) for 3 sec minimum, then turning on again.

6. Inducer speed operation—If cycle starts in low heat,

inducer speed reduces slightly after flame sense. If cycle

starts in high heat, inducer speed increases 15 sec after

flame sense. The reduction in speed in low heat is to

optimize combustion for maximum efficiency.

A93036

Fig. 42—Condensate Trap Heat Tape

SEQUENCE OF OPERATION

7. Blower on delay—The blower starts 60 sec after flame

sense if cycle started in low heat or 35 sec after flame sense

if cycle started in high heat.

CAUTION: Furnace control must be grounded for

proper operation, or control will lock out. Control is

grounded through green wire routed to gas valve and

burner box screw.

NOTE: The blower starts at approximately 400-500 RPM. After

20 sec, the motor is turned off for 1/10 of a sec where a coast down

calibration is done to evaluate resistance of the conditioned air

duct system. The microprocessor then determines blower RPM

required to provide proper airflow for heating mode.

Using schematic diagram (see Fig. 24), follow sequence of

operation through different modes. This furnace has a new control

system. Read and follow wiring diagram carefully.

8. Electronic Air Cleaner—The EAC-1 terminal is energized

whenever the blower operates.

NOTE: If 115-v power supply to furnace or blower access panel

switch is interrupted during a call for heat, blower operates at

low-heat speed for 60 sec when power is restored before heating

cycle is resumed.

9. Blower off delay—When thermostat is satisfied, the

R-W/W1 signal is terminated, de-energizing gas valve

(stopping gas flow to burners), and HUM terminal is

de-energized.

—31—

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The blower reduces its speed to low-heat RPM. The blower

and EAC remain operating 90, 135, 180, or 225 sec

(depending on blower off time selection). The furnace is

factory set for a 90-sec blower off delay.

NOTE: Ignition sequence repeats 3 additional times before lock-

out occurs. Lockout automatically resets after 3 hr, or can be

manually reset by turning 115-v or 24-v power off (not at

thermostat) for 3 sec minimum, then turning on again. Fault codes

will not flash in emergency heat mode.

10. Post purge—The inducer continues operating for 15 sec

after gas valve is de-energized.

8. Blower off delay—When thermostat is satisfied, the

R-W/W1 signal is terminated, de-energizing gas valve

(stopping gas flow to burners), and HUM terminal is

de-energized. The blower stops immediately.

III. HEATING MODE—TWO STAGE

The control center provides 2-stage heating using a single-stage

thermostat. The control center maximizes comfort while optimiz-

ing efficiency to meet the demands of conditioned area when a

thermostat R-W/W1 signal is received.

9. Post purge—Post purge does NOT occur. The inducer

stops immediately.

If thermostat control over furnace staging is desired, a 2-stage

thermostat can be used. When control center receives a thermostat

R-W/W1 and R-W2 signal, high heat is energized and when a

R-W/W1 signal alone is received, low heat is energized. This

method overrides microprocessor control of high or low heat.

V. COOLING MODE

A. Single-Speed Applications

When thermostat calls for cooling, the R-G and R-Y/Y2 circuits

close.

NOTE: When using 2-stage thermostat operation with R-W/W1

and R-W2 signals, setup switch SW-2 MUST be in ON position.

1. Cooling unit—The cooling unit starts when thermostat

R-Y signal is received.

The heat cycle operates as stated in Heating Mode section.

2. Blower on—The control center starts blower immediately

when it receives an R-Y/Y2 and R-G signal. The blower

starts at approximately 400-500 RPM. After 20 sec, the

blower is turned off for 1/10 of a sec where a coast down

calibration is done to evaluate resistance of the conditioned

air duct system. The microprocessor then determines

blower RPM required to provide selected cooling airflow.

To allow for greater comfort, 2-stage thermostat control is recom-

mended when zone systems are used.

IV. EMERGENCY HEAT MODE

NOTE: The furnace should not be operated in emergency heat

mode for extended periods of time. Operation is only recom-

mended to provide heat until replacement components can be

obtained or fault resolved.

NOTE: In cooling mode, the microprocessor adjusts blower RPM

to operate at 400 CFM per ton as selected on A/C setup switches.

See Air Conditioning Setup Switches section. There is also a chart

on wiring diagram. (See Fig. 24.)

In this mode, the microprocessor is bypassed and motors operate at

full speed with high-heat operation. The heat exchangers, motors,

and electronics can be overstressed and may reduce the life of

components if operated for an extended period.

NOTE: If Y/Y2 thermostat lead is not connected to furnace

control center, blower motor operates in continuous fan speed and

indoor coil freeze-up may occur.

NOTE: No safeties are bypassed when using emergency heat

mode.

3. Electronic Air Cleaner—The EAC-1 terminal is energized

Emergency heat mode can be selected using setup switch SW-4.

SW-4 should be used when a fault condition exists or difficult to

resolve problems occur. This allows heating until fault can be

corrected.

whenever blower operates.

4. Cooling unit—The cooling unit stops when thermostat R-Y

signal is terminated.

In emergency heat mode, the normal heat mode outlined in

Heating Mode section is not followed. The following sequence

will occur:

5. Blower off delay—When thermostat is satisfied, the

R-Y/Y2 and R-G signals are terminated, and blower re-

mains operating for 90 sec.

When thermostat calls for heat, the R-W/W-1 circuits close.

B. Two-Speed Applications

1. Prepurge period—The inducer motor is turned on IMME-

DIATELY operating at maximum speed, closing low- and

high-pressure switches. Prepurge begins 25 sec after high-

pressure switch closes.

For details on 2-speed cooling applications, refer to Fig. 43.

VI. HEAT PUMP MODE

A. Single-Speed Applications

2. Blower on—The blower motor is turned on IMMEDI-

ATELY and slowly increases to maximum speed as soon as

a call for heat is received. No blower calibration occurs.

When furnace is operating in heat pump heating mode, R-Y/Y2

and R-G circuits are closed energizing heat pump, and blower

operates at cooling speed. When heat pump defrost is required,

R-W/W1 circuits close starting gas heat cycle, and blower adjusts

to low-heat speed.

3. Electronic Air Cleaner—The EAC-1 terminal does not

operate in emergency heat mode.

4. Humidifier—The HUM terminal is energized IMMEDI-

1. Prepurge period—The inducer motor is turned on and

slowly comes up to speed. When low-pressure switch

closes, inducer motor RPM is noted by microprocessor, and

a 25 sec prepurge period begins. The RPM is used to

evaluate vent system resistance. This evaluation is then

used to determine required RPM necessary to operate

inducer in low-heat mode.

ATELY.

5. Ignitor warm up—The HSI is energized for a 17 sec

warm-up period after prepurge period is completed.

6. Ignition sequence—After HSI warm-up period has com-

pleted, the gas valve is energized, permitting gas flow to

burners where it is ignited. After 5 sec, the HSI is

de-energized, and a 2-sec flame-sensing period begins.

NOTE: The heat cycle can start in either high or low heat. If a

high-heat cycle is initiated, inducer continues increasing its speed

after low-pressure switch closes. When high-pressure switch

closes, inducer motor RPM is noted by microprocessor before the

25 sec prepurge period begins. The RPM is used to evaluate vent

system resistance. This evaluation is used to determine required

RPM necessary to operate inducer in high-heat mode.

NOTE: Emergency heat mode only operates in high heat.

7. Flame sensing—When burner flame is sensed, control

center holds gas valve open. If burner flame is not sensed,

control center de-energizes gas valve and ignition sequence

is repeated.

—32—

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b. R-W/W1 with R-Y/Y2 and R-G signals terminated—

The blower continues to operate completing a normal

blower off delay.

VARIABLE

SPEED

THERMOSTAT

2-SPEED

THERMOSTAT

2-SPEED AIR

CONDITIONER

11. Post purge—The inducer continues operating for 15 sec

after gas valve is de-energized.

B. Two-Speed Applications

For details on 2-speed heat pump applications, refer to Fig. 44.

VARIABLE

SPEED

2-SPEED

THERMOSTAT

HEAT PUMP

THERMOSTAT

W/W1

Y/Y2

W/W1

Y/Y2

A94302

Fig. 43—Wiring Schematic for 2-Speed

Cooling Applications

2. Humidifier—The HUM terminal is energized after inducer

prepurge period is completed.

3. Ignitor warm up—After prepurge period, HSI is energized

for 17 sec.

4. Ignition sequence—After HSI warm-up period is com-

pleted, the gas valve is energized, permitting gas flow to the

burners where it is ignited. After 5 sec, the HSI is

de-energized, and a 2-sec flame-sensing period begins.

A94303

Fig. 44—Wiring Schematic for 2-Speed

Heat Pump Applications

VII. CONTINUOUS FAN MODE

5. Flame sensing—When burner flame is sensed, control

center holds gas valve open.

1. Operating with continuous fan only—

If burner flame is not sensed, control center de-energizes

gas valve, and ignition sequence is repeated.

a. Call for continuous fan—The thermostat closes R-G

circuit.

6. Blower off period—Ten sec after gas valve is energized,

the blower stops for 25 sec to allow heat exchangers to

warm up.

b. Blower on—The blower starts immediately.

NOTE: The blower starts at approximately 400-500 RPM. After

20 sec, the motor is turned off for 1/10 of a sec where a coast down

calibration is done to evaluate resistance of the conditioned air

duct system. The microprocessor then determines blower RPM

required to provide proper airflow for heating mode.

7. Blower on delay—After blower off period, blower starts.

NOTE: The blower starts at approximately 400-500 RPM. After

20 sec, the motor is turned off for 1/10 of a sec where a coast down

calibration is done to evaluate resistance of the conditioned air

duct system. The microprocessor then determines blower RPM

required to provide proper airflow for heating mode.

NOTE: The continuous fan speed is the same as low-heat speed

unless it is field adjusted to another desired airflow. See Continu-

ous Fan Setup Switches section. There is also a chart on wiring

diagram. (See Fig. 24.)

8. Electronic Air Cleaner—The EAC-1 terminal is energized

c. Electronic Air Cleaner—The EAC-1 terminal is ener-

gized whenever blower operates, regardless of operating

mode.

whenever blower operates.

9. Inducer speed operation—If cycle starts in low heat,

inducer speed reduces slightly after the flame sense. If cycle

starts in high heat, inducer speed increases 15 sec after

flame sense. The reduction in speed in low heat is to

optimize combustion for maximum efficiency.

2. Operating with continuous fan (R-G) and call for heat

(R-W/W1) is received—Same as heat pump mode except

blower on delay is 10 sec less than heat mode. After call for

heat (R-W/W1) is terminated, the blower remains operating

at low-heat speed for selected blower off delay before

resuming continuous fan speed.

10. Call for heat terminated—When the call for heat is

satisfied, the R-W/W1 signal is terminated, de-energizing

gas valve (stopping gas flow to burners), and HUM terminal

is de-energized.

3. Operating with continuous fan (R-G) and call for cool-

ing (R-Y/Y2) is received—See Cooling Mode section.

After call for cooling (R-Y/Y2) is terminated, the blower

remains operating at cooling speed for 90 sec before

resuming continuous fan speed.

a. R-W/W1 signal terminated with R-Y/Y2 and R-G

still present—The blower changes its speed to cooling

RPM.

—33—

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VIII. COMPONENT TEST

XI. ZONE MODE

All components are functionally operated except gas valve with

component test feature.

When setup switch SW-5 MZ is in ON position, blower motor

control is the same as above except with the following exceptions:

This feature helps diagnose a system problem in case of a

component failure.

1. While blower is operating in either low heat or continuous

fan, the coast down calibration is performed once a minute

to update blower RPM for zone damper position changes

during a given cycle unless the blower pulse width to

blower motor is greater than 60 percent. This prevents

nuisance faults from occurring when a high continuous fan

CFM has been selected.

NOTE: Setup switch SW-1 MUST be in OFF position or Fault

Code 22 (setup error) will occur.

NOTE: NO thermostat signal may be present at control center,

and all blower time delay off periods must be completed.

To initiate component test feature, proceed with the following:

1. Leave 115-v power to furnace turned on.

2. Remove main furnace door.

2. While blower is operating in either high heat or cooling,

blower pulse width to blower motor is frozen when blower

RPM is within 10 percent of calculated blower RPM for 5

sec.

3. Remove blower access panel.

START-UP PROCEDURES

I. GENERAL

4. Turn setup switch SW-6 to ON position.

5. Manually close blower access panel door switch. Use a

piece of tape to hold switch closed.

1. Furnace must have a 115-v power supply properly con-

nected and grounded.

WARNING: Blower access panel door switch opens

115-v power to control center. No component operation

can occur. Caution must be taken when manually closing

this switch for service purposes. Failure to follow this

warning could result in personal injury or death.

NOTE: Proper polarity must be maintained for 115-v wiring. If

polarity is incorrect, control center fault indicator light flashes

rapidly and furnace does not operate.

2. Thermostat wire connections at terminals R, W/W1, G, and

Y/Y2 must be made at 24-v terminal block on control

center.

When items 1-5 have been completed, the following will occur:

3. Natural gas service pressure must not exceed 0.5 psig

(14-in. wc), but must be no less than 0.16 psig (4.5-in. wc).

1. The control center goes through a brief self-test. This

self-test takes approximately 2 sec to complete. After door

switch is closed, red (microprocessor) LED briefly comes

on. Then green LED comes on for 1 sec, followed by 1 sec

where both green and yellow LEDs are on. During this time,

the microprocessor is checking itself.

4. Blower access panel must be in place to complete 24-v

electrical circuit to furnace.

CAUTION: These furnaces are equipped with a manual

reset limit switch in burner box. This switch opens if an

overheat condition (rollout) occurs in burner enclosure.

Correct inadequate combustion-air supply or improper

venting condition and reset switch. DO NOT jumper this

switch.

2. Inducer motor operates for 20 sec at low speed, operates for

20 sec at high speed, then turns off.

3. Hot surface ignitor is energized for 15 sec, then de-

energized.

4. Main blower motor operates for 20 sec at low speed,

operates for 20 sec at high speed, then turns off.

Before operating furnace, check each manual reset switch for

continuity. If necessary, press button to reset switch.

5. After component operation test is completed, 1 or more

fault codes (11, 22, 41, or 42) will flash. See service label

on back of main furnace door for explanation of fault codes.

II. SELECT SETUP SWITCH POSITIONS

A. Air Conditioning (A/C) Setup Switches

NOTE: To repeat component test, turn setup switch SW-6 to OFF

and then back to ON.

The air conditioning setup switches are used to match furnace

airflow to cooling unit used. This furnace will provide 400 CFM

per selected air conditioning tonnage.

After component test, perform the following:

1. Release blower panel access door switch and turn setup

switch SW-6 to OFF position.

To set the desired cooling airflow:

1. Remove main furnace door and blower access panel.

2. Locate A/C setup switches on control center. (See Fig. 25.)

3. Determine air conditioning tonnage used.

2. If applicable, replace blower access panel and check LED

status by removing plug in blower access panel.

3. Reinstall main furnace door if all LEDs are off, indicating

furnace is ready to operate when a signal from thermostat is

received.

4. Use Table 8 or wiring schematic to determine proper setup

position of A/C switches. (See Fig. 24 and 45.)

NOTE: Excessive airflow caused by improper A/C switch setup

may cause condensate blow off in cooling mode.

IX. BYPASS HUMIDIFIER MODE

When setup switch SW-3 BPH is in ON position, RPM calculated

for low heat is multiplied by 1.15 for all furnace model sizes. This

compensates for increased return-air temperature caused by by-

passed air supply.

5. Replace main furnace door and blower access panel.

NOTE: EAC-1 terminal is energized whenever blower operates.

HUM terminal is only energized when gas valve is energized.

X. DEHUMIDIFICATION MODE

B. Continuous Fan (CF) Setup Switches

If dehumidification input is energized with a 24-vac input, RPM

calculated for cooling and continuous fan is multiplied by 0.85 for

all furnace model sizes. This compensates for high humidity

conditions during cooling operation.

The CF setup switches are used to select desired airflow when

thermostat is in continuous fan mode. This setup feature allows

continuous fan airflow to be adjusted. To set desired continuous

fan airflow:

—34—

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TABLE 8—AIR CONDITIONING (A/C) AIRFLOW SETUP SWITCH POSITION

A/C SETUP

SWITCH POSITION

AIR

ALLOWABLE FURNACE MODEL SETUP

CONDITIONER CFM AIRFLOW

(TONS)

A/C-1 A/C-2 A/C-3

042040

3 Tons

042060

3 Tons

042080

3 Tons

060080

5 Tons

060100

5 Tons

060120

5 Tons

1200 or

2000

Default

OFF

1200 CFM 1200 CFM 1200 CFM 2000 CFM 2000 CFM 2000 CFM

1-1/2

600

800

OFF

—

2-1/2

1000

1200

1400

1600

2000

OFF

3-1/2

OFF

—

X—Indicates allowable selection.

TABLE 9—CONTINUOUS FAN (CF) AIRFLOW SETUP SWITCH POSITION

CF SETUP

ALLOWABLE FURNACE MODEL SETUP

SWITCH POSITION

CONTINUOUS

FAN (CFM)

CF-1

CF-2

OFF

CF-3

OFF

042040

042060

042080

060080

060100

060120

Default

600

OFF

565*

515*

690*

—

860*

—

1035*

—

800

OFF

1000

1200

1400

1600

2000

OFF

—

* Add 15% additional CFM when Bypass Humidifier switch SW-3 on control board is used.

X—Indicates allowable selection.

3. See Table 10 for setup switch description. (See Fig. 24 and

45.)

4. Replace main furnace door and blower access panel.

NOTE: If a bypass humidifier is used, setup switch SW-3 (BPH)

should be in ON position. This prevents nuisance limit trips caused

by the increased temperature in return air resulting from bypass.

NOTE: If modulating dampers are used, setup switch SW-5 (MZ)

should be in ON position. This allows furnace control center to

compensate for modulating dampers. The control re-calibrates for

new system static conditions once every minute while operating in

low-heat or continuous fan modes.

OFF

III. PRIME CONDENSATE TRAP WITH WATER

A95198

Fig. 45—Example of Setup Switch in OFF Position

CAUTION: Condensate trap must be PRIMED or

proper draining may not occur. The condensate trap has 2

internal chambers which can ONLY be primed by pour-

ing water into the inducer drain side of condensate trap.

1. Remove main furnace door and blower access panel.

2. Locate CF setup switches on control center. (See Fig. 25.)

3. Determine desired continuous fan airflow.

4. Use Table 9 or wiring schematic to determine proper setup

position of CF switches. (See Fig. 24 and 45.)

1. Remove upper inducer housing drain connection cap. (See

Fig. 46.)

NOTE: The CF switches are factory set to provide continuous fan

airflow equal to low-heat mode.

2. Connect field-supplied 1/2-in. ID tube to upper inducer

housing drain connection.

5. Replace main furnace door and blower access panel.

3. Insert field-supplied funnel into tube.

C. Setup Switches (SW)

4. Pour 1 quart of water into funnel/tube. Water should run

through inducer housing, overfill condensate trap, and flow

into open field drain. (See Fig. 47.)

The control center has 8 setup switches that may be set to meet the

application requirements. Position these setup switches for the

appropriate requirement.

5. Remove funnel and tube from inducer housing and replace

drain connection cap and clamp.

1. Remove main furnace door and blower access panel.

2. Locate setup switches on control center. (See Fig. 25.)

—35—

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TABLE 10—SETUP SWITCH DESCRIPTION

SETUP

SWITCH NO.

NORMAL

POSITION

DESCRIPTION OF USE

SW-1

(FLT)

Turn switch to ON for fault history display. No thermostat signal can be

present for fault history display.

OFF

SW-2

(LOW)

OFF

Turn switch to ON to lock furnace in low-heat mode only.

Turn switch to ON when a bypass humidifier is used. This compensates

for higher return-air temperature and provides 5 percent more airflow in

low-heat mode only.

SW-3

(BPH)

Turn switch to ON to bypass microprocessor control. Furnace will oper-

ate at high heat only with main blower and inducer motor operating at

maximum RPM. NO safeties are bypassed.

SW-4

(EMER HEAT)

OFF

Turn switch to ON when modulating dampers are used. In this mode,

main blower speed is recalculated once every minute while furnace is in

low-heat or continuous fan mode.

SW-5

(MZ)

Turn switch to ON to initiate component test. Furnace will operate in-

ducer motor for 20 sec at low speed, operate inducer motor for 20 sec at

high speed, energize HSI for 15 sec, operate blower for 20 sec at low

speed, and operate blower for 20 sec at high speed. SW-1 must be in

OFF position. No thermostat signal can be present for component test to

be initiated.

SW-6

(COMP TEST)

OFF

SW-7 and -8

(Blower Off Delay)

Adjust switches to provide desired heating mode blower off delay time,

90, 135, 180, or 225 sec.

See Table 11

TABLE 11—BLOWER OFF DELAY SETUP SWITCH

POSITION

DESIRED HEATING

MODE BLOWER

OFF DELAY (SEC)

SETUP SWITCH (SW-7 AND -8) POSITION

SW-7

SW-8

OFF

135

180

225

OFF

A94208

A94209

Fig. 46—Inducer Housing Drain Tube

Fig. 47—Filling Condensate Trap

—36—

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IV. PURGE GAS LINES

e. Turn low-heat adjusting screw (5/64 hex Allen wrench)

counterclockwise (out) to decrease input rate or clock-

wise (in) to increase input rate.

If not previously done, purge the lines after all connections have

been made and check for leaks.

LOW-FIRE

ON/OFF

SWITCH

WARNING: Never purge a gas line into a combustion

chamber. Never use matches, candles, flame, or other

sources of ignition for the purpose of checking leakage.

Use a soap-and-water solution to check for leakage.

Failure to follow this warning could result in fire,

explosion, personal injury, or death.

ADJUSTMENT

ALLEN SCREW

(UNDER CAP)

HIGH-FIRE

ADJUSTMENT

ALLEN SCREW

(UNDER CAP)

INLET

PRESSURE

TAP

V. ADJUSTMENTS

A. Set Gas Input Rate

Furnace gas input rate on rating plate is for installations at altitudes

up to 2000 ft.

In the U.S.A., the input rating for altitudes above 2000 ft must be

reduced by 2 percent for each 1000 ft above sea level.

In Canada, the input rating must be derated by 5 percent for

altitudes of 2000 ft to 4500 ft above sea level.

Furnace input rate must be within ±2 percent of input on furnace

rating plate.

BURNER

1. Determine natural gas orifice size and manifold pressure for

correct input.

ENCLOSURE

REFERENCE

a. Obtain yearly heat value average (at installed altitude)

from local gas supplier.

PRESSURE TAP

MANIFOLD

PRESSURE

TAP

b. Obtain yearly specific gravity average from local gas

supplier.

A97386

→

Fig. 48—Redundant Automatic Gas Valve

c. Verify furnace model. Table 12 can only be used for

model 355MAV Furnaces.

NOTE: DO NOT set low-heat manifold pressure less than 1.3-in.

wc or more than 1.7-in. wc for natural gas. If manifold pressure is

outside this range, change main burner orifices.

d. Find installation altitude in Table 12.

NOTE: For Canada altitudes of 2000 to 4500 ft, use U.S.A.

altitudes of 2001 to 3000 ft in Table 12.

e. Find closest natural gas heat value and specific gravity in

Table 12.

CAUTION: DO NOT bottom out gas valve regulator

adjusting screw. This can result in unregulated manifold

pressure and result in excess overfire and heat exchanger

failures.

f. Follow heat value and specific gravity lines to point of

intersection to find orifice size and low- and high-heat

manifold pressure settings for proper operation.

NOTE: If orifice hole appears damaged or it is suspected to have

been redrilled, check orifice hole with a numbered drill bit of

correct size. Never redrill an orifice. A burr-free and squarely

aligned orifice hole is essential for proper flame characteristics.

EXAMPLE: (0—2000 ft altitude)

Heating value = 1050 Btu/cu ft

Specific gravity = 0.62

Therefore: Orifice No. 45

f. Turn setup switch SW-2 to OFF position after complet-

ing low-heat adjustment.

Manifold pressure: 3.6-in. wc for high heat

1.5-in. wc for low heat

* Furnace is shipped with No. 45 orifices. In this example,

all main burner orifices are the correct size and do not need

to be changed to obtain proper input rate.

g. Jumper R and W2 thermostat connections on control

center. (See Fig. 25.) This keeps furnace locked in

high-heat operation.

h. Turn high-heat adjusting screw (5/64 hex Allen wrench)

counterclockwise (out) to decrease input rate or clock-

wise (in) to increase rate.

g. Check and verify burner orifice size in furnace. NEVER

ASSUME ORIFICE SIZE; ALWAYS CHECK AND

VERIFY.

NOTE: DO NOT set high-heat manifold pressure less than 3.2-in.

wc or more than 3.8-in. wc for natural gas. If manifold pressure is

outside this range, change main burner orifices.

2. Adjust manifold pressure to obtain input rate.

a. Remove burner enclosure front.

i. When correct input is obtained, replace caps that conceal

gas valve regulator adjustment screws. Main burner

flame should be clear blue, almost transparent. (See Fig.

49.)

NOTE: Manifold pressure MUST always be measured with the

burner box cover REMOVED.

b. Remove caps that conceal adjustment screws for low-

and high-heat gas valve regulators. (See Fig. 48.)

3. Verify natural gas input rate by clocking gas meter.

NOTE: Be sure all pressure tubing, combustion-air and vent

pipes, and burner enclosure front are in place when checking input

by clocking gas meter.

c. Turn setup switch SW-2 on control center to ON

position. (See Fig. 25.) This keeps furnace locked in

low-heat operation.

a. Calculate high-altitude adjustment (if required).

UNITED STATES

d. Jumper R and W/W1 thermostat connections on control

center to start furnace.

—37—

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TABLE 12—MODEL 355MAV ORIFICE SIZE AND MANIFOLD PRESSURE FOR CORRECT INPUT

(TABULATED DATA BASED ON 20,000 BTUH HIGH HEAT/13,000 BTUH LOW HEAT PER BURNER

DERATED 2% FOR EACH 1000 FT ABOVE SEA LEVEL)

SPECIFIC GRAVITY OF NATURAL GAS

AVG GAS

ALTITUDE

RANGE

(FT)

0.58

Manifold

0.60

Manifold

0.62

Manifold

0.64

Manifold

Pressure

High/Low

0.66

Manifold

Pressure

High/Low

HEAT VALUE

AT ALTITUDE

(BTU/CU FT)

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Pressure

High/Low

Pressure

High/Low

Pressure

High/Low

850

875

3.7/1.5

3.5/1.5

3.7/1.6

3.5/1.5

3.4/1.4

3.2/1.3

3.7/1.6

3.5/1.5

3.3/1.4

3.2/1.3

3.6/1.5

3.8/1.6

3.6/1.5

3.4/1.4

3.7/1.6

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.5

3.3/1.4

3.7/1.6

3.2/1.4

3.7/1.6

3.5/1.5

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.4

3.7/1.6

3.6/1.5

3.4/1.4

3.2/1.4

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.7/1.6

3.5/1.5

3.4/1.4

3.2/1.3

3.7/1.6

3.5/1.5

3.4/1.4

3.2/1.4

3.7/1.6

3.5/1.5

3.8/1.6

3.6/1.5

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.5/1.5

900

925

950

975

1000

1025

1050

1075

1100

2000

SPECIFIC GRAVITY OF NATURAL GAS

0.60 0.62 0.64

Manifold

AVG GAS

HEAT VALUE

AT ALTITUDE

(BTU/CU FT)

ALTITUDE

RANGE

(FT)

0.58

0.66

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Pressure

High/Low

U.S.A.

Altitudes

2001

775

800

825

850

875

900

925

950

975

1000

1025

3.8/1.6

3.5/1.5

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.4

3.7/1.5

3.5/1.5

3.3/1.4

3.7/1.6

3.6/1.5

3.2/1.4

3.7/1.5

3.4/1.5

3.7/1.6

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.4

3.7/1.6

3.3/1.4

3.8/1.6

3.6/1.5

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.4

3.7/1.6

3.5/1.5

3.4/1.4

3.2/1.3

3.4/1.4

3.2/1.4

3.7/1.5

3.5/1.5

3.7/1.6

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.5/1.5

3.3/1.4

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.6/1.5

3.4/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3000

Canada

Altitudes

2000

4500

SPECIFIC GRAVITY OF NATURAL GAS

0.60 0.62 0.64

Manifold

AVG GAS

HEAT VALUE

AT ALTITUDE

(BTU/CU FT)

ALTITUDE

RANGE

(FT)

0.58

0.66

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Pressure

High/Low

750

775

800

825

850

875

900

925

950

975

1000

3.7/1.6

3.5/1.5

3.7/1.6

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.4

3.6/1.5

3.5/1.5

3.8/1.6

3.6/1.5

3.4/1.4

3.6/1.5

3.4/1.4

3.2/1.4

3.7/1.6

3.5/1.5

3.3/1.4

3.2/1.3

3.6/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.8/1.6

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.5

3.3/1.4

3.7/1.6

3.4/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.7/1.5

3.5/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.4/1.4

3.2/1.4

3.5/1.5

3.2/1.4

3.7/1.6

3.5/1.5

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.3

3.7/1.5

3.5/1.5

3.3/1.4

3001

4000

—38—

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TABLE 12—MODEL 355MAV ORIFICE SIZE AND MANIFOLD PRESSURE FOR CORRECT INPUT Continued

(TABULATED DATA BASED ON 20,000 BTUH HIGH HEAT/13,000 BTUH LOW HEAT PER BURNER

DERATED 2% FOR EACH 1000 FT ABOVE SEA LEVEL)

SPECIFIC GRAVITY OF NATURAL GAS

AVG GAS

ALTITUDE

RANGE

(FT)

0.58

Manifold

0.60

Manifold

0.62

Manifold

0.64

Manifold

Pressure

High/Low

0.66

Manifold

Pressure

High/Low

HEAT VALUE

AT ALTITUDE

(BTU/CU FT)

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Pressure

High/Low

Pressure

High/Low

Pressure

High/Low

725

750

775

800

825

850

875

900

925

950

3.7/1.5

3.4/1.4

3.7/1.6

3.5/1.5

3.2/1.4

3.7/1.6

3.5/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.8/1.6

3.5/1.5

3.8/1.6

3.6/1.5

3.4/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.4

3.6/1.5

3.2/1.4

3.7/1.5

3.4/1.4

3.7/1.6

3.5/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.3/1.4

3.2/1.3

3.3/1.4

3.8/1.6

3.5/1.5

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.3

3.6/1.5

3.4/1.5

3.3/1.4

3.4/1.4

3.2/1.4

3.7/1.5

3.4/1.4

3.7/1.6

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.4

4001

5000

SPECIFIC GRAVITY OF NATURAL GAS

0.60 0.62 0.64

Manifold

AVG GAS

HEAT VALUE

AT ALTITUDE

(BTU/CU FT)

ALTITUDE

RANGE

(FT)

0.58

0.66

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Pressure

High/Low

700

725

750

775

800

825

850

875

900

925

950

975

1000

3.6/1.5

3.4/1.4

3.6/1.5

3.4/1.4

3.2/1.3

3.6/1.5

3.4/1.4

3.2/1.4

3.6/1.5

3.4/1.4

3.7/1.6

3.5/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.7/1.6

3.5/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.8/1.6

3.6/1.5

3.5/1.5

3.2/1.3

3.6/1.5

3.4/1.4

3.6/1.5

3.4/1.4

3.2/1.4

3.6/1.5

3.4/1.5

3.3/1.4

3.7/1.5

3.5/1.5

3.8/1.6

3.6/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.7/1.6

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.3

3.6/1.5

3.4/1.4

3.7/1.6

3.4/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.6/1.5

3.4/1.4

3.2/1.4

3.7/1.5

3.5/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.8/1.6

5001

6000

SPECIFIC GRAVITY OF NATURAL GAS

0.60 0.62 0.64

Manifold

AVG GAS

HEAT VALUE

AT ALTITUDE

(BTU/CU FT)

ALTITUDE

RANGE

(FT)

0.58

0.66

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Pressure

High/Low

650

675

700

725

750

775

800

825

850

875

3.2/1.3

3.6/1.5

3.8/1.6

3.6/1.5

3.3/1.4

3.8/1.6

3.5/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.3/1.4

3.7/1.6

3.4/1.5

3.7/1.6

3.4/1.5

3.2/1.4

3.7/1.5

3.4/1.5

3.2/1.4

3.6/1.5

3.4/1.4

3.8/1.6

3.6/1.5

3.8/1.6

3.6/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.3

3.5/1.5

3.2/1.4

3.7/1.6

3.4/1.4

3.7/1.6

3.4/1.5

3.2/1.4

3.7/1.6

3.5/1.5

3.3/1.4

3.6/1.5

3.3/1.4

3.8/1.6

3.5/1.5

3.8/1.6

3.5/1.5

3.3/1.4

3.8/1.6

3.6/1.5

3.4/1.4

6001

7000

—39—

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TABLE 12—MODEL 355MAV ORIFICE SIZE AND MANIFOLD PRESSURE FOR CORRECT INPUT Continued

(TABULATED DATA BASED ON 20,000 BTUH HIGH HEAT/13,000 BTUH LOW HEAT PER BURNER

DERATED 2% FOR EACH 1000 FT ABOVE SEA LEVEL)

SPECIFIC GRAVITY OF NATURAL GAS

AVG GAS

ALTITUDE

RANGE

(FT)

0.58

Manifold

0.60

Manifold

0.62

Manifold

0.64

Manifold

Pressure

High/Low

0.66

Manifold

Pressure

High/Low

HEAT VALUE

AT ALTITUDE

(BTU/CU FT)

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Pressure

High/Low

Pressure

High/Low

Pressure

High/Low

625

650

675

700

725

750

775

800

825

850

3.8/1.6

3.5/1.5

3.8/1.6

3.5/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.3/1.4

3.6/1.5

3.4/1.4

3.3/1.4

3.7/1.6

3.4/1.4

3.6/1.5

3.4/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.3

3.5/1.5

3.4/1.4

3.8/1.6

3.5/1.5

3.8/1.6

3.5/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.3/1.4

3.7/1.5

3.5/1.5

3.2/1.4

3.6/1.5

3.4/1.4

3.6/1.5

3.4/1.4

3.8/1.6

3.6/1.5

3.4/1.4

3.2/1.3

3.6/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.7/1.6

3.5/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.3/1.4

7001

8000

SPECIFIC GRAVITY OF NATURAL GAS

0.60 0.62 0.64

Manifold

AVG GAS

HEAT VALUE

AT ALTITUDE

(BTU/CU FT)

ALTITUDE

RANGE

(FT)

0.58

0.66

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Pressure

High/Low

600

625

650

675

700

725

750

775

800

3.8/1.6

3.5/1.5

3.7/1.6

3.5/1.5

3.2/1.4

3.6/1.5

3.4/1.4

3.2/1.3

3.6/1.5

3.3/1.4

3.6/1.5

3.4/1.4

3.6/1.5

3.3/1.4

3.8/1.6

3.5/1.5

3.3/1.4

3.7/1.6

3.4/1.4

3.8/1.6

3.5/1.5

3.7/1.6

3.4/1.5

3.2/1.4

3.6/1.5

3.4/1.4

3.2/1.3

3.5/1.5

3.2/1.4

3.6/1.5

3.8/1.6

3.6/1.5

3.3/1.4

3.8/1.6

3.5/1.5

3.3/1.4

3.6/1.5

3.3/1.4

3.7/1.6

3.4/1.5

3.7/1.6

3.4/1.4

3.2/1.4

3.6/1.5

3.4/1.4

8001

9000

SPECIFIC GRAVITY OF NATURAL GAS

0.60 0.62 0.64

Manifold

AVG GAS

HEAT VALUE

AT ALTITUDE

(BTU/CU FT)

ALTITUDE

RANGE

(FT)

0.58

0.66

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Orifice

No.

Pressure

High/Low

575

600

625

650

675

700

725

750

775

3.8/1.6

3.5/1.5

3.7/1.6

3.4/1.4

3.8/1.6

3.6/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.2/1.4

3.6/1.5

3.8/1.6

3.5/1.5

3.3/1.4

3.7/1.6

3.4/1.5

3.2/1.4

3.6/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.7/1.5

3.4/1.4

3.8/1.6

3.6/1.5

3.3/1.4

3.7/1.6

3.5/1.5

3.2/1.3

3.6/1.5

3.8/1.6

3.5/1.5

3.3/1.4

3.7/1.6

3.4/1.5

3.2/1.4

3.6/1.5

3.3/1.4

3.7/1.6

3.4/1.4

3.6/1.5

3.4/1.4

3.8/1.6

3.5/1.5

3.3/1.4

9001

10,000

—40—

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EXAMPLE:

100,000 Btuh input furnace installed at 4300 ft.

Furnace Input

Rate at

Sea Level

Derate

X Multiplier =

Factor

Furnace Input Rate

at Installation

Altitude

100,000

0.91

91,000

CANADA

At installation altitudes from 2000 to 4500 ft, this

furnace must be derated 5 percent by an authorized Gas

Conversion Station or Dealer. To determine correct input

rate for altitude, see example above and use 0.95 as

derate multiplier factor.

BURNER

ORIFICE

b. Reinstall burner box cover.

A93059

NOTE: Clocking gas input rate MUST always be performed with

the burner box cover INSTALLED.

CAUTION: DO NOT redrill orifices. Improper drilling

(burrs, out-of-round holes, etc.) can cause excessive

burner noise and misdirection of burner flames. This can

result in flame impingement of burners and heat exchang-

ers, causing failures.

c. Check that gas valve adjustment caps are in place for

proper input to be clocked.

d. Obtain yearly heat value average for local gas supply.

NOTE: Be sure heating value of gas used for calculations is

correct for your altitude. Consult local gas utility for altitude

adjustment of gas heating value.

BURNER FLAME

BURNER

e. Check and verify orifice size in furnace. NEVER AS-

SUME THE ORIFICE SIZE. ALWAYS CHECK AND

VERIFY.

f. Turn off all other gas appliances and pilots.

g. Turn setup switch SW-2 to ON position. (See Fig. 25.)

This keeps furnace locked in low-heat operation.

h. Let furnace run for 3 minutes in low-heat operation.

i. Measure time (in sec) for gas meter to complete 1

revolution. Note reading.

j. Refer to Table 14 for cubic ft of gas per hr.

k. Multiply gas rate cu ft/hr by heating value (Btu/cu ft).

MANIFOLD

l. Turn setup switch SW-2 to OFF position and jumper R

and W2 thermostat connections. (See Fig. 25.) This keeps

furnace locked in high-heat operation. Repeat items h

through k for high-heat operation.

A89020

Fig. 49—Burner Flame

At altitudes above 2000 ft, this furnace has been ap-

proved for a 2 percent derate for each 1000 ft above sea

level. See Table 13 for derate multiplier factor and

example.

EXAMPLE: (High-heat operation at 0—2000 ft altitude)

Furnace input from rating plate is 100,000 Btuh

Btu heating input = Btu/cu ft X cu ft/hr

Heating value of gas = 975 Btu/cu ft

Time for 1 revolution of 2-cu ft dial = 70 sec

Gas rate = 103 cu ft/hr (from Table 14)

Btu heating input = 103 X 975 = 100,425 Btuh In this

example, the orifice size and manifold pressure adjustment

is within ±2 percent of the furnace input rate.

TABLE 13—ALTITUDE DERATE MULTIPLIER FOR U.S.A.

ALTITUDE

(FT)

% OF

DERATE

DERATE MULTIPLIER

FACTOR FOR U.S.A.*

0—2000

2001—3000

3001—4000

4001—5000

5001—6000

6001—7000

7001—8000

8001—9000

9001—10,000

1.00

0.95

0.93

0.91

0.89

0.87

0.85

0.83

0.81

NOTE: Measured gas inputs (high heat and low heat) must be

within ±2 percent of that stated on furnace rating plate when

installed at sea level or derated per that stated above when installed

at higher altitudes.

4—6

6—8

8—10

10—12

12—14

14—16

16—18

18—20

m. Remove jumper across R, W/W1, and W2 thermostat

connections to terminate call for heat.

* Derate multiplier factor is based on midpoint altitude for altitude range.

—41—

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TABLE 14—GAS RATE CU FT/HR

d. Ensure bypass humidifier switch (BPH) setup switch

SW-3 on control center is in ON position when a bypass

humidifier is used. (See Fig. 25 for switch location.)

SECONDS SIZE OF TEST DIAL SECONDS SIZE OF TEST DIAL

FOR 1

REVOLUTION cu ft cu ft cu ft REVOLUTION cu ft cu ft cu ft

e. Check Troubleshooting Guide for Variable-Speed

2-Stage Electronic Condensing Furnaces.

360

327

300

277

257

240

225

212

200

189

180

171

164

157

150

144

138

133

129

124

120

116

113

109

106

103

100

720 1800

655 1636

600 1500

555 1385

514 1286

480 1200

450 1125

424 1059

400 1000

100

102

104

106

108

144

141

138

136

133

131

129

126

124

122

120

116

112

109

106

103

100

360

355

346

340

333

327

321

316

310

305

300

290

281

273

265

257

250

243

237

231

225

220

214

209

205

200

196

192

188

184

180

178

173

170

167

C. Set Thermostat Heat Anticipator

The thermostat heat anticipator must be set to match the amp draw

of components in the R-W/W1 circuit. Accurate amp draw

measurements can be obtained at the thermostat subbase terminals

R and W.

379

360

343

327

313

300

288

277

267

257

248

240

232

225

218

212

206

200

195

189

185

180

176

172

167

164

160

157

153

150

147

947

900

857

818

783

750

720

692

667

643

621

600

581

563

545

529

514

500

486

474

462

450

439

429

419

409

400

391

383

375

367

Fig. 50 illustrates an easy method of obtaining thermostat amp

draw measurements. The amp reading should be taken after blower

motor has started and furnace is operating in low heat.

1. To operate furnace in low heat, turn setup switch SW-2 to

ON position (See Fig. 25) and connect ammeter leads

across thermostat subbase R-W.

2. See thermostat manufacturer’s instructions for adjusting the

heat anticipator and for varying heating cycle length.

NOTE: When using an electronic thermostat, set cycle rate for 3

cycles per hr.

3. Return setup switch SW-2 to OFF position and replace

thermostat on subbase.

THERMOSTAT SUBBASE

TERMINALS WITH

THERMOSTAT REMOVED

(ANITICIPATOR, CLOCK, ETC.,

MUST BE OUT OF CIRCUIT.)

HOOK-AROUND

AMMETER

110

112

116

120

164

161

155

150

B. Set Temperature Rise

CAUTION: Temperature rise must be within limits

specified on unit rating plate. Recommended operation is

at midpoint of rise or above. Failure to follow this caution

may result in condensing or overheating the heat ex-

changers.

10 TURNS

Furnace must operate within range of temperature rise specified on

the unit rating plate. Determine air temperature rise as follows:

FROM UNIT 24-V

CONTROL TERMINALS

1. Place thermometers in return and supply ducts as near

furnace as possible. Be sure thermometers do not see heat

exchanger so that radiant heat does not affect readings. This

practice is particularly important with straight-run ducts.

0.5 AMPS FOR THERMOSTAT

5.0 AMPS ON AMMETER

EXAMPLE:

ANTICIPATOR SETTING

10 TURNS AROUND JAWS

A96316

2. When thermometer readings stabilize, subtract return-air

temperature from supply-air temperature to determine air

temperature rise.

Fig. 50—Amp Draw Check with Ammeter

CHECK SAFETY CONTROLS

I. CHECK PRIMARY LIMIT CONTROL

NOTE: Temperature rise can be determined for low-fire opera-

tion by placing setup switch SW-2 on control center in ON

position. For high-heat operation, place setup switch SW-2 in OFF

position and jumper R-W2 on control center. DO NOT forget to

return setup switch to OFF position and remove R-W2 jumper

upon completion of testing. (See Fig. 25 for switch and terminal

location.)

This control shuts off the combustion control system and energizes

the air-circulating blower motor if furnace overheats.

1. The recommended method of checking this limit control is

to gradually block off return air after furnace has been

operating for a period of at least 5 minutes.

2. As soon as limit control has shut off burners, a 33 fault code

will appear on control center.

3. This furnace is capable of automatically providing proper

airflow to maintain the temperature rise within the range

specified on unit rating plate. If temperature rise is outside

this range, proceed as follows:

3. The return-air opening should be unblocked to permit

normal air circulation.

By using this method to check the limit control, it can be

established that the limit is functioning properly and the furnace

will operate safely if there is a restricted return-air supply or motor

failure. If the limit control does not function during this test, the

cause must be determined and corrected.

a. Check gas input for low- and high-heat operation.

b. Check derate for altitude if applicable.

c. Check all return and supply ducts for excessive restric-

tions causing static pressure greater than 0.5-in. wc.

—42—

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II. CHECK PRESSURE SWITCHES

7. Turn on 115-v power to furnace.

This control proves operation of the draft inducer. Check switch

operation as follows:

8. Reset thermostat to desired temperature.

1. Turn off 115-v power to furnace.

CHECKLIST

2. Remove control access door and disconnect inducer motor

12-pin wire harness at inducer motor.

1. Put away tools and instruments. Clean up debris.

2. Verify manual reset switch has continuity.

3. Turn on 115-v power to furnace.

4. Set thermostat to call for heat. When pressure switches are

functioning properly, fault code 42 will flash on control

center approximately 10 sec after thermostat switch is

closed. If either a fault code 31 or 32 is flashed when ICM

inducer motor is disconnected, the furnace will shut itself

down immediately. Determine the reason pressure switches

did not function properly and correct the condition.

3. Verify that blower and control access doors are properly

installed.

4. Cycle test furnace with room thermostat.

5. Check operation of accessories per manufacturer’s instruc-

tions.

6. Review User’s Manual with owner.

7. Leave literature packet near furnace.

5. Turn off 115-v power to furnace.

6. Reconnect inducer motor wire harness. Reinstall furnace

access door.

—43—

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CHECKLIST—INSTALLATION

LOAD CALCULATION

Heating Load (Btuh)

Condensate Drain

____________

________

Unit Level or Pitched Forward

Cooling Load (Btuh)

Internal Tubing Connections Free of Kinks

and Traps

________

Furnace Model Selection

External Drain Connection Leak Tight and

Sloped

COMBUSTION AND VENT PIPING

Termination Location

________

Condensate Trap Primed before Start-Up

Heat Tape Installed if Required

CHECKLIST—START-UP

________

Roof or Sidewall

Termination Kit — 2 Pipe or Concentric

Combustion-Air Pipe Length

Combustion-Air Pipe Elbow Quantity

Vent Pipe Length

Gas Input Rate

(Set Within 2 percent of Rating Plate)

________

Temperature Rise Adjusted

Thermostat Anticipator

Vent Pipe Elbow Quantity

Pipe Diameter Determined from Sizing Table

Pipe Sloped To Furnace

________

Anticipator Setting Adjusted or

Cycle Rate (3 Cycles per Hr) Selected

Safety Controls Check Operation

Primary Limit

Pipe Insulation

________

Over Ceilings

Pressure Switches

Low-Ambient Exposed Pipes

SERVICE TRAINING

Packaged Service Training programs are an excellent way to increase your

knowledge of the equipment discussed in this manual, including:

• Unit Familiarization

• Installation Overview

• Maintenance

• Operating Sequence

A large selection of product, theory, and skills programs is available, using popular

video-based formats and materials. All include video and/or slides, plus companion

book.

Classroom Service Training plus "hands-on" the products in our labs can mean

increased confidence that really pays dividends in faster troubleshooting, fewer

callbacks. Course descriptions and schedules are in our catalog.

CALL FOR FREE CATALOG 1-800-962-9212

[ ] Packaged Service Training

[ ] Classroom Service Training

A94328

Printed in U.S.A.

355m405

Catalog No. BDP-5335-500

—44—

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