Bryant BRYANT 355M-40-5, 355MAV Installation And Operating Instructions Manual

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UPFLOW

DOWNFLOW

HORIZONTAL

LEFT

AIRFLOW

HORIZONTAL

RIGHT

installation, start-up, and operating instructions

DELUXE 4-WAY MULTIPOISE VARIABLE-CAPACITY DIRECT-VENT CONDENSING GAS FURNACE

Cancels: II 355M-40-4 II 355M-40-5

355MAV

Series D

7-97

NOTE: Read the entire instruction manual before starting the installation.

This symbol → indicates a change since the last issue. 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

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

A93040

CANADIAN GAS ASSOCIATION

APPROVED

A93041

As an ENERGY STAR Partner, Bryant Heating & Cooling Systems Company has determined that this product meets the ENERGY STAR guidelines for energy efficiency.

Fig. 1—Multipoise Orientations

ama

CERTIFICATION OF MANUFACTURING SITE

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

—1—

⁄2"

⁄16"

AIRFLOW

⁄4" 26

⁄8"

⁄16"

⁄8"

OUTLET

2-IN. COMBUSTION-

TYP

⁄2-IN. DIA

GAS CONN

AIR CONN

⁄8-IN. DIA

⁄16"

19"

⁄16"

POWER CONN

2-IN. VENT CONN

⁄2-IN. DIA

THERMOSTAT ENTRY

⁄16"

⁄4" TYP 22

⁄16"

SIDE INLET

A93023

BOTTOM INLET

⁄4"

⁄2"

(DOWNFLOW &

OR ALTERNATE

TRAP LOCATION

/16"

-IN. DIA GAS CONN

⁄2

HORIZONTAL RIGHT)

CONDENSATE DRAIN

OUTLET

CONDENSATE

INLET

HANGING

(UPFLOW)

DRAIN LOCATION

FOR HORIZONTAL

DIMPLE LOCATORS

/16"

/2-In. rectangle.

/4-In. rectangle.

/2 x 19

/2 x 23

/2 x 12-In. rectangle.

/16"

⁄4"

TYP

⁄8"

TYP

⁄16"

⁄16"

TYP

⁄8"

⁄16"

TYP

⁄2"

⁄16"

/16"

DIMENSIONS (IN.)

Fig. 2—Dimensional Drawing

For 800 CFM--16-In. round or 14

For 1200 CFM--20-In. round or 14

For 1600 CFM--22-In. round or 14

For airflow requirements above 1800 CFM, use both side inlets, a

combination of 1 side inlet and the bottom, or the bottom only.

NOTES: Minimum return-air opening at furnace:

1.

2.

3.

⁄8-IN. DIA

POWER CONN

CONDENSATE

DRAIN TRAP

CONDENSATE DRAIN

TRAP LOCATION

(DOWNFLOW &

HORIZONTAL LEFT)

⁄16"

⁄4"

⁄2"

⁄16"

⁄2-IN. DIA

2-IN. COMBUSTION-

AIR CONN

GAS CONN

2-IN. VENT CONN

⁄8-IN. DIA

ACCESSORY

ENTRY

⁄16"

⁄2-IN. DIA THERMOSTAT

LOCATION

POWER ENTRY

⁄16"

(ALTERNATE

UPFLOW)

SIDE INLET

⁄2"

TYP

CONDENSATE

DRAIN LOCATION

(UPFLOW)

⁄4" TYP

⁄16" TYP

SIDE INLET

⁄4"

042060 17-1/2 15-7/8 16

042080 21 19-3/8 19-1/2

060080 21 19-3/8 19-1/2

060100 21 19-3/8 19-1/2

042040* 24-1/2* 22-7/8* 23*

UNIT SIZE A D E

060120 24-1/2 22-7/8 23

* These dimensions reflect the wider casing for the Trophy (96.6 percent AFUE) furnace.

—2—

SAFETY CONSIDERATIONS

Installing and servicing heating equipment can be hazardous due to gas and electrical components. Only trained and qualified personnel should install, repair, or service heating equipment. Untrained personnel can perform basic maintenance functions such as cleaning and replacing air filters. All other operations must be performed 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.

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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.

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.

Understand the signal words DANGER, WARNING, and CAUTION. 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

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.

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 electrostatic potential.

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.

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.

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

TO COMBUSTIBLE CONSTRUCTION

ALL POSITIONS:

Mimimum front clearance for service 30

inches (762mm).

140 size furnaces require 1 inch back

††

clearance to combustible materials.

Clearance arrows do not change with furnace orientation.

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.

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.

120 and 140 size Furnaces require 1 inch

bottom clearance to combustible materials.

323857-101 REV. B (LIT)

††

Clearance in inches

TOP/PLENUM

DESSUS/CHAMBRE D´AIR

BOTTOM

DESSOUS

MIN

†

Vent clearance to

combustibles 0".

A97378

→ Fig. 3—Clearances to Combustibles

—3—

recharges your body with static electricity (for example; DO NOT move or shuffle your feet, DO NOT touch ungrounded objects, etc.).

4. If you touch ungrounded objects (recharge your body with static electricity), firmly touch furnace again before touching control or wires.

5. Use this procedure for installed and uninstalled (ungrounded) furnaces.

6. Before removing a new control from its container, discharge 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.

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, recreation 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) applications 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.

Installer Packet includes:

Installation, Start-Up, and Operating Instructions Service and Maintenance Procedures User’s Information Manual Warranty Certificate

Loose Parts Bag includes: Quantity

Pressure tube extension 1 Collector box or condensate trap extension tube 1 Inducer housing drain tube 1 1/2-in. CPVC street elbow 2 Drain tube coupling 1 Drain tube coupling grommet 1 Vent and combustion-air pipe support 2 Combustion-air pipe perforated disk assembly 1

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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.

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.

Canadian installations must be made in accordance with NSCNGPIC and all authorities having jurisdiction.

These instructions cover minimum requirements for a safe installation 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.

CAUTION: Application of this furnace should be indoors 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 premature component failure.

WARNING: Improper installation, adjustment, alteration, 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.

II. UPFLOW APPLICATIONS

An upflow furnace application is where furnace blower is located below combustion and controls section of furnace, and conditioned air is discharged upwards.

A. Condensate Trap Location (Factory-Shipped Orientation)

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.

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—

BLOWER SHELF

CONDENSATE TRAP (INSIDE)

ALTERNATE DRAIN TUBE LOCATION

CONDENSATE TRAP

DRAIN TUBE LOCATION

UPFLOW APPLICATIONS

FURNACE DOOR

FIELD

DRAIN

CONN

EXTERNAL UPFLOW APPLICATIONS

SLOT FOR SCREW

HORIZONTAL

APPLICATION

(OPTIONAL)

WIRE TIE GUIDES (WHEN USED)

CONDENSATE TRAP

FURNACE

SIDE

FURNACE DOOR

FIELD

DRAIN

CONN

FURNACE SIDE

SIDE VIEW FRONT VIEW END VIEW FRONT VIEW

DOWNFLOW AND ALTERNATE

⁄4 OD COLLECTOR BOX TO TRAP RELIEF PORT

⁄2 OD INDUCER HOUSING DRAIN CONNECTION

⁄8 OD COLLECTOR BOX DRAIN CONNECTION

SCREW HOLE FOR UPFLOW OR DOWN- FLOW APPLICATIONS (OPTIONAL)

⁄2-IN. PVC OR CPVC

HORIZONTAL

APPLICATIONS

FRONT VIEW SIDE VIEW

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).

2. Condensate Trap Drain Tube The condensate trap drain connection must be extended for

field attachment by doing the following: a. Determine location of field drain connection. (See Fig. 2

or 5.)

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.

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

loose parts bag) in selected casing hole.

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

bag) through grommet so long end of coupling faces blower.

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 cemented to condensate trap drain connection.

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

A93026

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.

C. Condensate Trap Location (Alternate Upflow Orientation)

An alternate location for the condensate trap is the left-hand side of casing. (See Fig. 2 and 6.)

NOTE: If the alternate left-hand side of casing location is used, the factory-connected drain and relief port tubes must be disconnected and modified for attachment. See Condensate Trap Tubing (Alternate Upflow Orientation) section for tubing attachment.

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

1. Remove 3 tubes connected to condensate trap.

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 6.)

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.

—5—

PLUG

CAP

COLLECTOR BOX

DRAIN TUBE (BLUE

& WHITE STRIPED)

COLLECTOR BOX

TUBE (PINK)

PLUG

CAP

COLLECTOR BOX

DRAIN TUBE (BLUE

& WHITE STRIPED)

COLLECTOR BOX

TUBE (PINK)

COLLECTOR BOX

TUBE (GREEN)

INDUCER HOUSING 

(MOLDED) DRAIN 

TUBE (BEHIND 

COLLECTOR BOX 

DRAIN TUBE)

COLLECTOR BOX

DRAIN TUBE (BLUE)

COLLECTOR BOX

TUBE (GREEN)

FIELD-INSTALLED

FACTORY-SUPPLIED

DRAIN TUBE

COUPLING (LEFT

DRAIN OPTION)

FIELD-INSTALLED

FACTORY-SUPPLIED

DRAIN TUBE

FIELD-INSTALLED

FACTORY-SUPPLIED

⁄2 -IN. CPVC STREET

ELBOWS (2) FOR

LEFT DRAIN OPTION

FIELD-INSTALLED

FACTORY-SUPPLIED

COUPLING (RIGHT

CONDENSATE  TRAP

DRAIN TUBE

DRAIN OPTION)

A94213

Fig. 5—Factory-Shipped Upflow Tube Configuration

(Shown With Blower Access Panel Removed)

D. Condensate Trap Tubing (Alternate Upflow Orientation)

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

confirm location of these tubes.

1. Collector Box Drain Tube Connect collector box drain tube (blue label) to condensate

trap.

NOTE: On 17-1/2-in. wide furnaces ONLY, cut tube between corrugated sections to prevent kinks.

2. Inducer Housing Drain Tube a. Remove and discard LOWER (molded) inducer housing

drain tube which was previously connected to condensate trap.

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. c. Determine appropriate length, cut, and connect tube. d. Clamp tube to prevent any condensate leakage.

3. Relief Port Tube a. Connect relief port tube (green label) to condensate trap.

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

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

COLLECTOR BOX

DRAIN TUBE (GREEN)

CONDENSATE

TRAP

INDUCER

HOUSING

DRAIN TUBE

(VIOLET)

A94214

Fig. 6—Alternate Upflow Tube Configuration and

Trap Location

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

E. Condensate Trap Field Drain Attachment

Refer to Condensate Drain section for recommendations and procedures.

F. Pressure Switch Tubing

The LOWER collector box pressure tube (pink label) is factory connected to the pressure switch and should not require any modification.

NOTE: See Fig. 5 or 6 or tube routing label on main furnace door to check for proper connections.

G. Upper Collector Box and Inducer Housing (Unused) Drain Connections

UPPER COLLECTOR BOX DRAIN CONNECTION

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.

NOTE: See Fig. 5 or 6 or tube routing label on main furnace door to check for proper connections.

UPPER INDUCER HOUSING DRAIN CONNECTION

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.

—6—

COLLECTOR BOX

DRAIN TUBE (BLUE)

CAP

PLUG

COLLECTOR BOX

TUBE (GREEN)

COLLECTOR BOX

TUBE (PINK)

COLLECTOR BOX

DRAIN TUBE (BLUE

& WHITE STRIPED)

COLLECTOR BOX 

EXTENSION TUBE

CONDENSATE

TRAP

INDUCER HOUSING 

DRAIN TUBE (VIOLET)

COLLECTOR BOX TUBE (GREEN)

PLUG CAP

COLLECTOR BOX DRAIN TUBE (BLUE)

COLLECTOR BOX TUBE (PINK)

COLLECTOR BOX DRAIN TUBE (BLUE & WHITE STRIPED)

COLLECTOR BOX  EXTENSION TUBE

INDUCER HOUSING  DRAIN TUBE  (VIOLET)

CONDENSATE TRAP

COLLECTOR BOX  EXTENSION  DRAIN TUBE

DRAIN TUBE COUPLING

A94215

Fig. 7—Downflow Tube Configuration

(Left-Hand Trap Installation)

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

to check for proper connections.

H. Condensate Trap Freeze Protection

Refer to Condensate Drain Protection section for recommendations and procedures.

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.

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.

To relocate condensate trap from the blower shelf to desired location, perform the following:

1. Remove 3 tubes connected to condensate trap.

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, 7, or 8.)

4. Install casing hole filler cap into blower shelf hole where trap was removed.

5. Install condensate trap into desired casing hole by inserting tube connection stubs through casing hole and rotating until tabs snap into locking position.

B. Condensate Trap Tubing NOTE: See Fig. 7 or 8 or tube routing label on main furnace door

to check for proper connections.

1. Collector Box Drain Tube

Fig. 8—Downflow Tube Configuration

(Right-Hand Trap Installation)

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.

c. Connect LOWER collector box drain connection to

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

(a.) Connect LOWER collector box drain tube

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

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

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

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

→

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

(d.) Determine appropriate length and cut. (e.) Connect to condensate trap. (f.) 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.

A94216

(blue and white striped label) to condensate trap. Tube does not need to be cut.

loose parts bag) into collector box drain tube (blue and white striped label) which was previously plugged.

supplied in loose parts bag) to drain tube coupling, extending collector box drain tube for connection to condensate trap.

rectly from collector box drain to condensate trap as shown in Fig. 8.

—7—

b. Remove and discard UPPER (molded) inducer housing

drain tube which was previously connected to condensate trap.

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.

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

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

→

3. Relief Port Tube

C. Condensate Trap Field Drain Attachment

Refer to Condensate Drain section for recommendations and procedures.

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 disconnected 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 HORIZONTAL RIGHT applications.

NOTE: See Fig. 7 or 8 or tube routing label on main furnace door to check for proper connections.

Relocate tubes as described below.

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

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

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

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

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

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

7. Clamp tube to relief port connection.

E. Condensate Trap Freeze Protection

Refer to Condensate Drain Protection section for recommendations and procedures.

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

directly from inducer housing drain to conden-

sate trap as shown in Fig. 8. (b.) Determine appropriate length and cut. (c.) Connect tube to condensate trap. (d.) Clamp tube to prevent any condensate leakage.

Refer to Pressure Switch Tubing section for connection procedure.

to pressure switch.

previously connected to condensate trap relief port connection by splicing to small diameter tube (factory-supplied in loose parts bag).

sure switch connection labeled COLLECTOR BOX.

previously connected to pressure switch by splicing to remaining small diameter tube (factory-supplied in loose parts bag).

relief port connection.

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.

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.

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.

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 or 9.

To relocate condensate trap from the blower shelf to desired location, perform the following:

1. Remove 3 tubes connected to condensate trap.

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 9.)

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.

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.

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

supplied in loose parts bag) to drain tube coupling, extending collector box drain tube.

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

cut to appropriate length.

d. Clamp tube to prevent any condensate leakage.

2. Inducer Housing Drain Tube a. Remove and discard LOWER (molded) inducer housing

drain tube which was previously connected to condensate trap.

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. c. Determine appropriate length, cut, and connect tube. d. Clamp tube to prevent any condensate leakage.

3. Relief Port Tube 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).

—8—

b. Route extended collector box pressure tube to relief port

connection on condensate trap. c. Determine appropriate length, cut, and connect tube. d. Clamp tube to prevent any condensate leakage.

C. Condensate Trap Field Drain Attachment

Refer to Condensate Drain section for recommendations and procedures.

D. Pressure Switch Tubing

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.

E. Condensate Trap Freeze Protection

Refer to Condensate Drain Protection section for recommendations and procedures.

F. Construct a Working Platform

Construct working platform where all required furnace clearances are met. (See Fig. 3 and 10.)

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.

NOTE: Combustion-air and vent pipes are restricted to a minimum 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.)

PLUG

AUXILIARY "J" BOX RELOCATED HERE

V. HORIZONTAL RIGHT (SUPPLY-AIR DISCHARGE) APPLICATIONS

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.

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.

NOTE: In Canada, installations shall be in accordance with current NSCNGPIC Installation Codes and/or local codes.

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 or 11.

To relocate condensate trap from the blower shelf to desired location, perform the following:

1. Remove 3 tubes connected to condensate trap.

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.)

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.

CAP

COLLECTOR BOX DRAIN TUBE (BLUE AND WHITE STRIPED)

CONDENSATE

RELOCATE TUBE BETWEEN BLOWER SHELF AND INDUCER HOUSING FOR

TRAP



COLLECTOR BOX

EXTENSION TUBE

COLLECTOR

BOX EXTENSION

DRAIN TUBE

DRAIN TUBE COUPLING

COLLECTOR BOX TUBE (PINK)

040, 060, AND 080 HEATING INPUT FURNACES

Fig. 9—Horizontal Left Tube Configuration

—9—

COLLECTOR BOX TUBE (GREEN)

INDUCER HOUSING DRAIN TUBE (VIOLET)

COLLECTOR BOX DRAIN TUBE (BLUE)

A93353

MANUAL

SHUTOFF

GAS VALVE

COMBUSTION – AIR

SEDIMENT TRAP

INTAKE

5 3⁄4″

CONDENSATE TRAP

VENT



30″ MIN WORK AREA

DRAIN

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.

ACCESS OPENING FOR TRAP

NOTE: LOCAL CODES MAY REQUIRE A DRAIN PAN UNDER THE

FURNACE AND CONDENSATE TRAP WHEN A CONDENSING FURNACE IS INSTALLED ABOVE FINISHED CEILINGS.

Fig. 10—Attic Location and Working Platform

B. Condensate Trap Tubing NOTE: See Fig. 11 or tube routing label on main furnace door to

check for proper connections.

1. Collector Box Drain Tube 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 previously connected to condensate trap.

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.

b. Remove and discard UPPER (molded) inducer housing

drain tube which was previously connected to condensate trap.

c. Install cap and clamp on UPPER inducer housing drain

connection where molded drain tube was removed.

d. Use inducer housing drain extension tube (violet label

and factory-supplied in loose parts bag) to connect LOWER inducer housing drain connection to condensate trap.

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

condensate trap.

f. Clamp tube to prevent any condensate leakage.

A93031

3. Relief Port Tube Refer to Pressure Switch Tubing section for connection

procedure.

C. Condensate Trap Field Drain Attachment

Refer to Condensate Drain section for recommendations and procedures.

D. Pressure Switch Tubing

NOTE: See Fig. 11 or tube routing label on main furnace door to check for proper connections.

Relocate tubes as described below.

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

2. Extend collector box pressure tube (green label) which was previously connected to condensate trap relief port connection by splicing to small diameter tube (factory-supplied in loose parts bag).

3. Connect collector box pressure tube (green label) to pressure switch connection labeled COLLECTOR BOX.

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.

—10—

CAP

PLUG

COLLECTOR BOX DRAIN TUBE 

(BLUE AND WHITE STRIPED)

INDUCER HOUSING

DRAIN TUBE (VIOLET)

COLLECTOR BOX

EXTENSION TUBE

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

Refer to Condensate Drain Protection section for recommendations and procedures.

F. Construct a Working Platform

Construct working platform where all required furnace clearances are met. (See Fig. 3 and 10.)

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.

NOTE: Combustion-air and vent pipes are restricted to a minimum 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.)

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.

COLLECTOR BOX DRAIN TUBE (BLUE)

COLLECTOR BOX TUBE (GREEN)

COLLECTOR BOX TUBE (PINK)

CONDENSATE TRAP

LEVEL (0″)

TO

⁄2″ MAX

UPFLOW OR DOWNFLOW HORIZONTAL

FRONT

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.

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.

CAUTION: If these furnaces are used during construction 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 adhesives, paints, thinners, masonry cleaning materials, and many other solvents commonly used in the construction process. Excessive exposure to contaminated combustion air will result in safety and performance related problems.

LEVEL (0″)

TO

⁄2″ MAX

A93354

FRONT

A93025

—11—

FRONT

°F °F

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.

Provide ample space for servicing and cleaning. Always comply with minimum fire protection clearances shown on unit’s clearance to combustibles label. (See Fig. 3.) Locate furnace where available electric power and gas supplies meet specifications on furnace rating plate.

FRONT

32°F MINIMUM INSTALLED AMBIENT OR FREEZE PROTECTION REQUIRED

A93058

CAUTION: If these furnaces are installed in an unconditioned space where ambient temperatures may be 32°F or lower, freeze protection measures must be taken.

II. LOW-FIRE ONLY INSTALLATION

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.

B A C K

BACK

FRONT

A93043

WARNING: Do not install furnace on its back. Safety control operation will be adversely affected. Never connect return-air ducts to back of furnace. Failure to follow this warning could result in fire, personal injury, or death.

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.

NEVER assume the high-fire input rate is not important for low-fire-only installation.

III. FURNACE LOCATION RELATIVE TO COOLING EQUIPMENT

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.

—12—

IV. HAZARDOUS LOCATIONS

18-IN. MINIMUM

TO BURNERS

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 accordance with requirements of National Fire Protection Association, Inc.

A93044

⁄16″

1 3⁄4″

⁄4″

⁄16″

1 3⁄4″

Fig. 12—Leveling Legs

1. Determine application being installed from Table 1.

A89014

I. LEVELING LEGS (IF DESIRED)

INSTALLATION

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.

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.

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.

2. Construct hole in floor per dimensions specified in Table 1 and Fig. 13.

3. Construct plenum to dimensions specified in Table 1 and Fig. 13.

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.)

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.

—13—

FURNACE

CD5 OR CK5

COIL ASSEMBLY

OR KCAKC

COIL BOX

FURNACE

SHEET METAL

PLENUM

FLOOR

OPENING

COMBUSTIBLE

FLOORING

(OR COIL CASING

WHEN USED)

COMBUSTIBLE

FLOORING

DOWNFLOW

SUBBASE

SHEET METAL

PLENUM

FLOOR

OPENING

PLENUM

OPENING

FLOOR

OPENING

A96283

Fig. 13—Floor and Plenum Opening Dimensions

A96285

Fig. 14—Furnace, Plenum, and Subbase

Installed on a Combustible Floor

FURNACE

CASING

WIDTH

Upflow Applications 16 24-1/8 16-5/8 24-3/4

17-1/2

Downflow Applications on Combustible Flooring Using KGASB Subbase

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

Downflow Applications on Combustible Flooring NOT Using KGASB Subbase

Downflow Applications on Combustible Flooring Using KGASB Subbase

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

Downflow Applications on Combustible Flooring NOT Using KGASB Subbase

24-1/2

Downflow Applications on Combustible Flooring Using KGASB Subbase

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

Downflow Applications on Combustible Flooring NOT Using KGASB Subbase

Downflow Applications on Non-Combustible Flooring 15-7/8 19 16-1/2 19-5/8

Furnace with CD5 or CK5 Coil Assembly or KCAKC Coil Box

Upflow Applications 19-1/2 24-1/8 20-1/8 24-3/4

Downflow Applications on Non-Combustible Flooring 19-3/8 19 20 19-5/8

Furnace with CD5 or CK5 Coil Assembly or KCAKC Coil Box

Upflow Applications 23 24-1/8 23-5/8 24-3/4

Downflow Applications on Non-Combustible Flooring 22-7/8 19 23-1/2 19-5/8

Furnace with CD5 or CK5 Coil Assembly or KCAKC Coil Box

TABLE 1—OPENING DIMENSIONS (IN.)

APPLICATION

—14—

A96284

Fig. 15—Furnace, Plenum, and Coil

Assembly or Coil Box Installed

on a Combustible Floor

PLENUM OPENING FLOOR OPENING

ABCD

15-1/8 19 16-3/4 20-3/8

15-1/2 19 16-1/2 20

18-5/8 19 20-1/4 20-3/8

19 19 20 20

22-1/8 19 23-3/4 20-3/8

22-1/2 19 23-1/2 20

PERFORATED DISCHARGE DUCT FLANGE

III. INSTALLATION IN HORIZONTAL APPLICATIONS

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.)

210° MIN

Fig. 16—Duct Flanges

YES

A93029

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.

ANGLE IRON OR EQUIVALENT

(B)

(A) ROD LOCATION

USING DIMPLE LOCATORS (SEE DIMENSIONAL DWG FOR LOCATIONS)

(A) PREFERRED ROD LOCATION  (B) ALTERNATE ROD LOCATION

5 3⁄4″

(B)

(A)

DRAIN

(A)

(B)

/8-IN. HEX NUT

& WASHER (4)

REQD PER ROD

NOTES:

(A)

1. A 1 In. clearance minimum between top of furnace and combustible material. 

2. The entire length of furnace must be supported when furnace is used in horizontal position to ensure proper drainage.

(B)

ALTERNATE SUPPORT LOCATION FROM BACK

Fig. 17—Crawlspace Horizontal Application

/16-IN. MAX

⁄8-IN. ROD

ALTERNATE SUPPORT LOCATION 4-IN. MIN 8-IN. MAX

A93304

—15—

IV. FILTER ARRANGEMENT

BOTTOM CLOSURE PANEL

FRONT FILLER PANEL

CAUTION: Never operate unit without a filter or with blower access panel removed.

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.

TABLE 2—FILTER INFORMATION

FURNACE

CASING

WIDTH (IN.)

17-1/2 (1) 16 X 25 X 1† (1) 16 X 25 X 1 Cleanable

21 (1) 16 X 25 X 1 (1) 20 X 25 X 1† Cleanable

24-1/2 (2) 16 X 25 X 1† (1) 24 X 25 X 1 Cleanable

* 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.

FILTER SIZE (IN.)*

Side Return Bottom Return

FILTER TYPE

FRAMED

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.

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.)

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

3. Remove bottom closure panel.

4. Reinstall front filler panel and screws.

171⁄2-IN. WIDE  CASINGS ONLY:

INSTALL FIELD-SUPPLIED FILTER FILLER STRIP UNDER FILTER.

3″

/2″

1″

FILTER SUPPORT

241⁄2-IN. WIDE  CASINGS ONLY:

CUT AND FOLD FACTORY-PROVIDED FILTERS AS SHOWN TO DESIRED SIZE.

FILTER RETAINER

→ Fig. 19—Bottom Filter Arrangement

WASHABLE FILTER

A96030

WASHABLE

FILTER

Fig. 18—Filter Installed for Side Inlet

FILTER RETAINER

A93045

A93047

Fig. 20—Removing Bottom Closure Panel

—16—

VI. GAS PIPING

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.

TABLE 3—MAXIMUM CAPACITY OF PIPE*

NOMINAL

IRON

PIPE SIZE

(IN.)

1/2 0.622 175 120 97 82 73 3/4 0.824 360 250 200 170 151

1 1.049 680 465 375 320 285 1-1/4 1.380 1400 950 770 660 580 1-1/2 1.610 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.

INTERNAL DIAMETER

(IN.)

LENGTH OF PIPE (FT)

10 20 30 40 50

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.

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.

GAS SUPPLY

MANUAL SHUTOFF VALVE (REQUIRED)

SEDIMENT TRAP

UNION

Fig. 21—Typical Gas Pipe Arrangement

→

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.

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: 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.

A93324

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.

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.)

CAUTION: If a flexible connector is required or allowed by authority having jurisdiction, black iron pipe shall be installed at gas valve and extend a minimum of 2 in. outside furnace casing.

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.

—17—

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.

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.

Make all 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.

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.

115-VOLT

SINGLE

PHASE

115-VOLT 

FUSED

DISCONNECT

SWITCH

(WHEN REQUIRED)

FURNACE

CONTROL

CENTER

FIELD 24-VOLT WIRING FIELD 115-, 208/230-, 460-VOLT WIRING FACTORY 24-VOLT WIRING FACTORY 115-, 208/230-, 460-VOLT WIRING

FIVE

WIRE

THREE-WIRE

NOTE 5

WCR GY

THERMOSTAT TERMINALS

FUSED DISCONNECT

HEATING

ONLY

AUXILIARY J-BOX

W/W1

NOTE



Y/Y2

24-VOLT

NOTE 1

TWO WIRE

GND

CONDENSING

UNIT

TERMINAL BLOCK

NOTES:

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.

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

→ Fig. 22—Heating and Cooling Application Wiring Diagram

FIELD-SUPPLIED

GND

208/230- OR 460-VOLT THREE PHASE

208/230- VOLT SINGLE PHASE

A96338

ELECTRIC

DISCONNECT

SWITCH

COPPER

WIRE ONLY

ALUMINUM

WIRE

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.

→

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.

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.

A93033

FACTORY

INSTALLED

LOCATION

ALTERNATE FIELD LOCATION

A93051

Fig. 23—Relocating J-Box

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).

—18—

SCHEMATIC DIAGRAM

(NATURAL GAS & PROPANE)

MTR1

412

PL7

EQUIPMENT GROUND

T 1

T 2

NOTE #2

ILK

TO 115 VAC FIELD DISCONNECT

654

PL1

NOTE #2

RED

GRN

BLUE

TRAN HPS

BLK

WHT

BLK

PL7

BLK

HSI

WHT GRN

YEL

PL9

BRN

12104 612

ORN

FU2

FUSED DISCONNECT

SWITCH (WHEN REQ’D)

BLK

WHT

BLK

WHT

ILK

MTR1

FSE

ALS

FRS

RED

JUMPERS

1-4 2-5 3-6

PL2-4

LPS

NOTE #11

FSE

LGPS

(WHEN USED)

NOTE #11

PL2-1

PL2-2

PL1-1

CPU2

GVR

HSIR

HUMR

Control will auto-reset after three hours.

1. If any of the original equipment wire is replaced use wire rated for 105°C.

2. Use only copper wire between the disconnect switch and the furnace junction box (JB).

3. This wire must be connected to furnace sheet metal for control to prove flame.

4. Symbols are electrical representation only.

5. Solid lines, inside circuit board PCB are printed circuit board traces and are not depicted as shown in the legend.

6. Replace only with a 3 AMP fuse.

7. Inductor used on all 060 or -20 airflow units.

8. Blower-on delay, gas heating 60 seconds low heat, 35 seconds high heat, cooling or heat pump 2 seconds..

9. Blower-off delay, gas heating 90, 135, 180 or 225 seconds, cooling or heat pump 90 seconds.

10. Ignition-lockout will occur after four consecutive unsuccessful trials-for-ignition.

HSI

SEC-2

TRAN

24VAC

115VAC

PL9

PL12

PL4

HSIR

MTR2

PL13

PCB

NOTE #5

PL11

D.C.

POWER

SUPPLY

CPU2

SW - 4

EMER. HEAT

IND

NOTE #7

PL11

12345

PL10

B1 7

CPU1

12345

SEC-1

FU1

NOTE #6

PL1-9

EAC-1 EAC-2

ALS

EAC

FRS

PL3

PL1-11

PCB

D.C. POWER

HUMR

HUM

PL1-7

NOTE #5

SUPPLY

GVR

PL1-2

Y/Y2

PL1-10

CPU1

HPS

NOTE #3

EAC

W/W1

A96276

322296-101 REV. B

11. Factory connected when LGPS not used.

NOTES:

(WHEN USED)

SEC.

180

8 7

BPH

FLT

CFM

TON

OFF

CFM

OFF

RED

3168

12543

225

OFF

OFF-DELAY

BLOWER

COMP. TEST EMER. HEAT

LOW HEAT

CFM

2000

TON

213

OFF

CFM

1000

TON

2-1/2

213

OFF

VIO

YEL

ORN

MTR2

32 1

BLU

SEC.

OFF

654

Fig. 24—Wiring Diagram

PL5

PL6

PL6 3-CIRCUIT COMM. CONNECTOR

PL7 12-CIRCUIT INDUCER MTR CONNECTOR

PL9 2-CIRCUIT HSI CONNECTOR

PL10 9-CIRCUIT BLOWER ADAPTER CONNECTOR

PL11 1-CIRCUIT INDUCTOR SPLICE CONNECTOR

PL12 5-CIRCUIT BLOWER POWER CONNECTOR

PL13 16-CIRCUIT BLOWER CTRL. CONNECTOR

SW1 MANUAL SWITCH, FAULT DISPLAY, SPST-(N.O.)

SW2 MANUAL SWITCH, LOW HEAT, SPST-(N.O.)

SW3 MANUAL SWITCH, BYPASS HUMIDIFIER, SPST-(N.O. )

JUNCTION

UNMARKED TERMINAL

PCB TERMINAL (FACTORY CONNECTED)

FACTORY WIRING (115 VAC)

FACTORY WIRING (24 VAC)

FIELD WIRING (115 VAC)

CONDUCTOR ON PCB

FIELD WIRING SCREW TERMINAL

TERMINAL BLOCK - MARKED TERMINAL

FIELD GROUND

EQUIPMENT GROUND

FIELD SPLICE

PCB TERMINAL (FIELD CONNECTION)

PLUG RECEPTACLE

SW4 MANUAL SWITCH, EMERGENCY HEAT, SPST-(N.O.)

SW5 MANUAL SWITCH, MULTIPLE ZONE, SPST-(N.O.)

SW6 COMPONENT TEST, SPST-(N.O.)

SW7-8 MANUAL SWITCH, BLOWER OFF-DELAY, SPST-(N.O.)

TRAN TRANSFORMER - 115VAC/24VAC

PCB

PL13

LPS

YEL

RED

T 1

BLK

WHT

BLK

EAC2

EAC1

1.5 AMP

BLU

BRN

LGPS

NOTE #11

HUMGR

ORN

1234

YEL

PL2

T 2

WHT BLK

RED BRN

10 11

RED

GRN

PL4

BRN

ORN

YEL

456

BLU

123

PL1

WHT

GRN

RED

GRN

NOTE #3

ORN

Y/Y2

W/W1CW2

BLK

WHT

RED

BLUE

BLOWER

BRN

NOTE #6

FUSE

24VAC-3A

SEC-1

FU1

SEC-2

A/C AND CF

SELECTION CHART

POS.

SWITCH

PL3 5BLU 4YEL 3VIO 2ORN

A/C AND CF

1RED

SELECTION CHART

POS.

SWITCH

RED

ORN

VIO

YEL

YEL BLU

BLU

WHT

BLK

987654321

PL11

PL10

ORN

NOTE #11

OFF-DELAY

SELECTION CHART

234 1

(1-4)

LEDS

1200

213

A/C CF A/C CF

213

CF A/C

DEFAULT

123 123

CFM

TON

OFF

NOTE #7

IND.

135

OFF

8 7 6

45 3

(1-8)

CFM

1400

TON

3-1/2

213

OFF

600

CFM

TON2TON

1-1/2

213

OFF

PL11

OFF

1600

213

800

213

PL12

GRN

WHT BLK

YEL

SIZE

042040

042060

042080

060100

060080

MODEL

060120

—19—

LEGEND

A/C AIR CONDITIONING (ADJUSTABLE TONNAGE)

ALS AUXILIARY LIMIT SWTICH OVERTEMP - MANUAL RESET SPST-(N.C )

CF CONTINUOUS FAN (ADJUSTABLE CFM)

CPU1 MAIN MICROPROCESSOR & CIRCUITRY

CPU2 IGNIT ION MICROPROCESSOR & CIRCUITRY

DH DEHUMIDIFICATION CONNECTION (24VAC .02 AMPS)

EAC-1 ELECTRONIC AIR CLEANER CONNECTION (115 VAC 1.5 AMP MAX.)

EAC-2 ELECTRONIC AIR CLEANER CONNECTION (COMMON)

FRS FLAME ROLLOUT SWITCH - MANUAL RESET, SPST-(N.C.)

FSE FLAME PROVING SENSOR ELECTRODE

FU1 FUSE, 3 AMP, AUTOMOTIVE BLADE TYPE, FACTORY INSTALLED

FU2 FUSE OR CIRCUIT BREAKER CURRENT INTERRUPT DEVICE (FIELD INSTALLED & SUPPLIED)

GV GAS VALVE

GVR GAS VALVE RELAY, DPST-(N.O.)

HI GAS VALVE HIGH STAGE OPERATOR

HPS HIGH HEAT PRESSURE SWITCH, SPST-(N.O.)

HSI HOT SURFACE IGNITOR (115 VAC)

HSIR HOT SURFACE IGNITOR RELAY, SPST-(N. O. )

HUM 24VAC HUMIDIFIER CONNECTION (.5 AMP. MAX.)

HUMR HUMIDIFIER RELAY, SPST-(N.O.)

ILK BLOWER ACCESS PANEL INTERLOCK SWITCH, SPST-(N.O.)

IND INDUCTOR (NOTE #7)

JB JUNCTION BOX

LEDS LIGHT EMITTING DIOES FOR ST ATUS CODES

LGPS LOW GAS PRESSURE SWITCH, SPST (N.O.)

LPS LOW HEAT PRESSSURE SWITCH, SPST-(N.O.)

LS LIMIT SWITCH, AUTO RESET, (N.C.)

MTR1 MOTOR (ICM) INDUCER

MTR2 MOTOR (ICM) BLOWER

PCB PRINTED CIRCUIT BOARD

PL1 11-CIRCUIT CONNECTOR

PL2 4-CIRCUIT PRESSURE SWITCH CONNECTOR

PL3 5-CIRCUIT BLOWER MTR CONNECTOR

PL4 2-CIRCUIT HSI CONNECTOR

PL5 6-CIRCUIT MODEL PLUG

TABLE 4—ELECTRICAL DATA

UNIT SIZE

042040 115—60—1 127 104 8.9 12.0 14 31 15 042060 115—60—1 127 104 8.9 12.0 14 31 15 042080 115—60—1 127 104 8.9 12.0 14 31 15 060080 115—60—1 127 104 13.8 17.9 12 32 20 060100 115—60—1 127 104 13.8 18.1 12 32 20 060120 115—60—1 127 104 11.6 15.3 12 37 20

* 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.

VOLTS— HERTZ—

PHASE

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.

III. ACCESSORIES

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.) Strip EAC power lead insulation approximately 1/4

in.

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

lead’s butt connector and crimp to secure.

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

in.

EAC-ELECTRONIC AIR CLEANER TERMINALS

(115-VAC 1 AMP MAX)

OPERATING

VOLTAGE RANGE

Maximum* Minimum*

MAXIMUM

UNIT

AMPS

UNIT

AMPACITY†

MINIMUM

WIRE

SIZE

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

NOTE: If desired, cut butt connectors off factory leads and strip insulation approximately 1/4 in and use field-supplied wire nuts to connect.

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

is the following procedure: (1.) Remove 2 screws securing the control box to

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

(3.) Strip EAC power leads insulation approximately

NOTE: The control center EAC terminals are sized for 12 gage maximum, solid or stranded wire.

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

HOT SURFACE IGNITOR CONNECTOR

MAXIMUM WIRE

LENGTH (FT)‡

MAXIMUM FUSE OR

CKT BKR AMPS**

leads’s butt connector and crimp to secure.

furnace blower shelf.

control center EAC terminals.

1/8 in.

MAIN BLOWER

CONTROL WIRE

CONNECTOR

CONTINUOUS

FAN (CF) SETUP

SWITCHES

TRANSFORMER

24-V CONNECTORS

COMMUNICATION

CONNECTOR

Fig. 25—Control Center

115-V CONNECTORS

PRESSURE SWITCH CONNECTOR

HUM

24-V THERMOSTAT TERMINALS

W/W1 Y/Y2

24V

COM

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

MODEL PLUG

HUM-HUMIDIFIER TERMINAL (24-VAC 0.5 AMP MAX)

A93062

—20—

EAC1

EAC2

A93053

Fig. 26—EAC Terminals on Control Center

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

terminals by depressing terminal’s arm with a screwdriver or finger. (See Fig. 26.)

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

2 screws removed earlier.

2. Humidifier (HUM) 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.

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.

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.

I. REMOVAL OF EXISTING FURNACES FROM COMMON VENT SYSTEMS

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 operation, while any other appliances connected to the venting system are not in operation:

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 restriction, leakage, corrosion, and other deficiencies which could cause an unsafe condition.

3. If practical, close all building doors and windows and all doors between the space in which the appliance(s) connected to the venting system are located and other spaces of the building. Turn on clothes dryers and any appliance not

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.

5. Test for draft hood equipped appliance spillage at the draft hood relief opening after 5 minutes of main burner operation. 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 dampers, and any other gas-burning appliance to their previous conditions of use.

7. If improper venting is observed during any of above tests, the venting system must be corrected.

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 NSCNGPIC.

II. COMBUSTION-AIR AND VENT PIPING A. General

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.

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.

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.

Furnace combustion-air and vent pipe connections must be attached as shown in Fig. 28. Combustion-air intake plug fitting and inducer housing alternate vent cap may need to be relocated in some applications.

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.

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.

—21—

TABLE 5—COMBUSTION-AIR AND VENT PIPE

TERMINATION CLEARANCES

LOCATION

Above grade level or above anticipated snow depth

Dryer vent 33 From plumbing vent stack 33 From any mechanical fresh air intake 16 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

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

From service regulator vent, electric and gas meters, and relief equipment

Above grade when adjacent to public walkway

* 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.

CLEARANCE (FT)

U.S.A. Canada

11†

4* 6‡

Select 1 vent pipe connection and

NOTE: Select 1 vent pipe connection and

1 combustion-air pipe connection.

AIR

COMBUSTION-

AIR

VENT

COMBUSTION-

AIR

FLOW

HORIZONTAL-LEFT DISCHARGE HORIZONTAL-RIGHT DISCHARGE

FLOW

COMBUSTION-

AIR

UPFLOW DOWNFLOW

AIR

VENT

NOTE:

1 combustion-air pipe connection.

VENT

COMBUSTION-

AIR

AIR

FLOW

COMBUSTION-

VENT

COMBUSTION-

AIR

AIR

FLOW

A96187

Fig. 28—Combustion-Air and Vent Pipe Connections

FURNACE

NOT IN HORIZONTAL SECTION

PIPE DIAMETER

TRANSITION IN

VERTICAL SECTION

Fig. 27—Combustion-Air and Vent Pipe Diameter

Transition Location and Elbow Configuration

CAUTION: Combustion air must not be taken from

inside structure because that air is frequently contaminated 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 products. Locate combustion-air inlet as far as possible from swimming pool and swimming pool pump house. Excessive exposure to contaminated combustion air will result in safety and performance related problems.

A93034

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.

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.

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.

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.

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—

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, 1-1/2in. pipe is not allowed with 5 elbows, but 2-in. pipe is good for 68 ft with 5 elbows.

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.

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.

b. Reposition combustion-air intake housing plug fitting in

appropriate unused intake housing connection.

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.

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.

VENT PIPE

HORIZONTAL TO ROOF HORIZONTAL TO SIDEWALL

12″ MIN

COMBUSTION-AIR PIPE

12″ MIN

VENT PIPE

COMBUSTION-AIR PIPE COMBUSTION-AIR PIPE

COMBUSTION-AIR PIPE

VENT PIPE

12″ MIN

VENT PIPE

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.

VERTICAL TO SIDEWALLVERTICAL TO ROOF

A96230

Fig. 29—Short Vent (5 to 8 Ft) System

—23—

ALTITUDE

0 to 2000

ALTITUDE

2001 to 3000

ALTITUDE

3001 to 4000

ALTITUDE

4001 to 5000‡

ALTITUDE

5001 to 6000‡

See notes on next page.

UNIT SIZE

042040

042060 042080

060080 060100

060120

UNIT SIZE

042040

042060 042080

060080 060100

060120

UNIT SIZE

042040

042060 042080

060080 060100

060120

UNIT SIZE

042040

042060 042080

060080 060100

060120

UNIT SIZE

042040

042060 042080

060080 060100

060120

TABLE 6—MAXIMUM ALLOWABLE PIPE LENGTH (FT)

TERMINATION

TYPE

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 3-In.

Concentric

TERMINATION

TYPE

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 3-In.

Concentric

TERMINATION

TYPE

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 3-In.

Concentric

TERMINATION

TYPE

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 3-In.

Concentric

TERMINATION

TYPE

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 3-In.

Concentric

PIPE DIAMETER

(IN.)*

1-1/2 50 45 40 35 30 25

2 707070707070

1-1/2 50 45 40 35 30 25

2 707070707070

1-1/2 30 25 20 15 10 5

2 707070707070

2 454035302520 2-1/2 70 70 70 70 70 70 2-1/2 10 NA NA NA NA NA

3 353015NANANA

3† 70 70 70 70 70 70

PIPE DIAMETER

(IN.)*

1-1/2 45 40 35 30 25 20

2 70707070 70 70 1-1/2 45 40 35 30 25 20

2 70707070 70 70 1-1/2 26 21 16 11 6 NA

2 70707070 70 70

2 40353025 20 15 2-1/2 70 70 70 70 70 70

3 312612NANANA

3† 63 62 62 61 61 61

PIPE DIAMETER

(IN.)*

1-1/2 42 37 32 27 22 17

2 70707070 70 70 1-1/2 42 37 32 27 22 17

2 70707070 70 70 1-1/2 25 20 15 10 5 NA

2 70707070 70 70

2 38332823 18 13 2-1/2 70 70 70 70 70 70

3 292410NANANA

3† 59 59 58 57 57 56

PIPE DIAMETER

(IN.)*

1-1/2 40 35 30 25 20 15

2 7070707070 70 1-1/2 40 35 30 25 20 15

2 7070707070 70 1-1/2 23 18 13 8 NA NA

2 7070707070 68

2 3631262116 11 2-1/2 70 70 70 70 70 70

3† 56 55 54 53 52 52

PIPE DIAMETER

(IN.)*

1-1/2 37 32 27 22 17 12

2 7070707070 70 1-1/2 37 32 27 22 17 12

2 7070707070 70 1-1/2 22 17 12 7 NA NA

2 7070707068 63

2 3328231813 8 2-1/2 70 70 70 70 70 70

3† 53 52 50 49 48 47

123456

1234 5 6

12345 6

NUMBER OF 90° ELBOWS

—24—

TABLE 6—MAXIMUM ALLOWABLE PIPE LENGTH (FT) Continued

ALTITUDE

UNIT SIZE

042040

042060

6001 to 7000‡

042080 060080

060100

060120

ALTITUDE

UNIT SIZE

042040

042060

7001 to 8000‡

042080 060080

060100

060120

ALTITUDE

UNIT SIZE

042040

042060

8001 to 9000‡

042080 060080

060100

060120

ALTITUDE

UNIT SIZE

042040

042060

9001 to 10000‡

042080 060080

060100

060120

* 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.

TERMINATION

TYPE

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 3-In.

Concentric

TERMINATION

TYPE

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 3-In.

Concentric

TERMINATION

TYPE

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 3-In.

Concentric

TERMINATION

TYPE

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 2-In.

Concentric

2 Pipe or 3-In.

Concentric

PIPE DIAMETER

(IN.)*

12345 6

1-1/2 35 30 25 20 15 10

2 7070686766 64

1-1/2 35 30 25 20 15 10

2 7070686766 64

1-1/2 20 15 10 5 NA NA

2 7070686762 57 2 3126211611 6

2-1/2 70 70 68 67 66 64

3† 49 48 47 45 44 43

PIPE DIAMETER

(IN.)*

1234 5 6

1-1/2 32 27 22 17 12 7

2 66656362 60 59

1-1/2 32 27 22 17 12 7

2 66656362 60 59

1-1/2 18 13 8 NA NA NA

2 66656362 57 52 2 29241914 9 NA

2-1/2 66 65 63 62 60 59

3† 46 44 43 41 40 38

PIPE DIAMETER

(IN.)*

1234 5 6

1-1/2 30 25 20 15 10 5

2 62605856 55 53

1-1/2 30 25 20 15 10 5

2 62605856 55 53

1-1/2 17 12 7 NA NA NA

2 62605856 51 46 2 27221712 7 NA

2-1/2 62 60 58 56 55 53

3† 43 41 39 37 35 34

PIPE DIAMETER

(IN.)*

1234 5 6

1-1/2 27 22 17 12 7 NA

2 57555351 49 47

1-1/2 27 22 17 12 7 NA

2 57555351 49 47

1-1/2 15 10 5 NA NA NA

2 57555351 46 41 2 241914 9 NANA

2-1/2 57 55 53 51 49 47

3† 39 37 35 33 31 29

NUMBER OF 90° ELBOWS

—25—

COMBUSTION-AIR INTAKE HOUSING PLUG FITTING

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: DO NOT OVERTIGHTEN SCREW. Breakage to intake housing or fitting may cause air leakage to occur.

A plugged drain connection has been provided on this fitting for use when moisture is found in combustion-air intake pipe and combustion box.

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.

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.)

COMBUSTION – AIR

3/8" ID TUBE

3/16"

DRILL

4″

TRAP

TO OPEN

MIN

DRAIN

Fig. 30—Intake Housing Plug Fitting Drain

INTAKE HOUSING

BURNER BOX

COMBUSTION – AIR PIPE 

A93035

2. Attach vent pipe as follows: a. Determine location of vent pipe connection to inducer

housing as shown in Fig. 28 for application.

b. Reposition neoprene inducer housing outlet cap and

clamp to appropriate unused inducer housing connection. Tighten clamp.

WARNING: Inducer housing outlet cap 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.

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.

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

neoprene coupling and clamp in inducer housing. Tighten clamp.

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.

NOTE: A 2-in. diameter pipe must be used within the furnace casing. Make all pipe diameter transitions outside furnace casing.

3. Working from furnace to outside, cut pipe to required length(s).

4. Deburr inside and outside of pipe.

5. Chamfer outside edge of pipe for better distribution of primer and cement.

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.

8. After pipes have been cut and preassembled, apply generous 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.

9. While cement is still wet, twist pipe into socket with 1/4 turn. Be sure pipe is fully inserted into fitting socket.

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.

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.

13. Slope combustion-air and vent pipes toward furnace a minimum of 1/4 in. per linear ft with no sags between hangers.

14. Use appropriate methods to seal openings where vent and combustion-air pipes pass through roof or sidewall.

III. CONCENTRIC VENT AND COMBUSTION-AIR TERMINATION KIT INSTALLATION

NOTE: If these instructions differ from those packaged with

termination kit, follow kit instructions. 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.

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

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.

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

—26—

MAINTAIN 12 IN. CLEARANCE ABOVE HIGHEST ANTICIPATED SNOW LEVEL OR GRADE, WHICHEVER IS GREATER.

90°

VENT

12 IN. SEPARATION BETWEEN BOTTOM OF COMBUSTION AIR AND BOTTOM OF VENT

BRACKET

COUPLING

12″ MINIMUM

OVERHANG OR ROOF

COMBUSTION-AIR (ELBOW PARALLEL TO WALL)

MAINTAIN 12 IN. CLEARANCE ABOVE HIGHEST ANTICIPATED SNOW LEVEL OR GRADE, WHICHEVER IS GREATER.

COMBUSTION-AIR

VENT

1″ MAXIMUM

12″ MINIMUM

OVERHANG OR ROOF

VERTICAL SEPARATION

BETWEEN COMBUSTION

MAXIMUM OF 24 IN. ABOVE ROOF.

AIR AND VENT 8 3/4″ FOR 3″ KIT 6 3/4″ FOR 2″ KIT

MAINTAIN 12 IN. MINIMUM

CLEARANCE ABOVE HIGHEST

ANTICIPATED SNOW LEVEL.

COUPLING

VENT

ROOF

18″ MAXIMUM

BRACKET

COMBUSTION AIR

Fig. 31—Roof Termination (Preferred)

VENT

COMBUSTION AIR

MAINTAIN 12 IN. (18 IN. FOR CANADA) MINIMUM CLEARANCE ABOVE HIGHEST ANTICIPATED SNOW LEVEL. MAXIMUM OF 24 IN. ABOVE ROOF.

Fig. 32—Concentric Vent and Combustion-Air Roof

Termination (Preferred)

OVERHANG OR ROOF

A93054

A87224

A93055

Fig. 33—Concentric Vent and Combustion-Air Side

Termination

BRACKET

90°

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

12″ MINIMUM

VENT

COMBUSTION-AIR

12 IN. SEPARATION BETWEEN BOTTOM OF COMBUSTION AIR AND BOTTOM OF VENT

MAINTAIN 12 IN. CLEARANCE ABOVE HIGHEST ANTICIPATED SNOW LEVEL OR GRADE, WHICHEVER IS GREATER.

A87225

—27—

A87226

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

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

TEMPERATURE AMBIENT*

UNIT SIZE

042040

042060

042080 060080

060100

060120

* 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.

WINTER DESIGN

TEMPERATURE

(°F)

20 2 2137425057

0 2 10 22 25 30 35

-20 2 5 14 17 21 25 20 2 3055617070

0 2 16 33 38 46 53

-20 2 9 23 26 33 38 20 2 3765707070

0 2 20 39 45 55 63

-20 2 1127313945 20 2-1/2 41 70 70 70 70

0 2-1/2 21 42 48 59 68

-20 2-1/2 11 28 33 41 49 20 3 4970707070

0 3 26 51 58 70 70

-20 3 1535405059

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.

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.

1. Determine combustion-air and vent pipe diameters, as stated above, using total pipe length and number of elbows.

2. Using winter design temperature (used in load calculations), find appropriate temperature for your application and furnace model.

3. Determine required insulation thickness for exposed pipe lengths.

NOTE: Pipe length (ft) specified for maximum pipe lengths located in unconditioned spaces cannot exceed total allowable pipe length as specified in Table 6.

B. Two-Pipe Termination Kit

1. Determine location for termination. Consideration of the following should be made when

determining an appropriate location for termination kit. 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 equipment.

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.

e. Termination kit should be positioned where vent vapors

are not objectionable.

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.

MAXIMUM PIPE

DIAMETER

(IN.)

INSULATION THICKNESS (IN.)†

0 3/8 1/2 3/4 1

Roof terminations—Loosely install pipe coupling on properly 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.

Sidewall terminations—Install bracket as shown in Fig. 34 or 35.

For applications using vent pipe option indicated by dashed lines in Fig. 34, rotate vent elbow 90° from position shown in Fig. 34.

4. Disassemble loose pipe fittings. Clean and cement using same procedures as used for system piping.

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

C. Concentric Vent/Air Termination Kit

1. Determine location for termination. Consideration of the following should be made when

determining an appropriate location for termination kit. 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 equipment.

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.

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.

3. Loosely assemble concentric vent/air termination components together using instructions in kit.

4. Slide assembled kit with rain shield REMOVED through hole.

—28—

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 appropriate 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.

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.

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.

Condensate trap MUST be used for all applications. An external trap is not required when connecting the field drain to

this condensate trap. 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.

When a condensate pump is required, select a pump which is approved for condensing furnace applications. To avoid condensate 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.

II. APPLICATION

The furnace, A/C, and humidifier drains may be combined and drained together. The A/C drain must have an external, fieldsupplied 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.

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.

32°F MINIMUM INSTALLED AMBIENT OR FREEZE PROTECTION REQUIRED

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.

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.

WARNING: Caution should be taken to prevent draining where slippery conditions may cause personal injuries. Excessive condensate draining may cause saturated soil conditions which may result in damage to plants.

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 recommendations.

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.)

3. Use wire ties to secure heat tape in place. Wire ties can be positioned in notches of condensate trap sides. (See Fig.

42.)

4. Wrap field drain pipe with remaining heat tape, approximately 1 wrap per ft.

5. When using field-supplied heat tape, follow heat tape manufacturer’s instructions for all other installation guidelines.

—29—

A96128

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

VENT

COMBUSTION AIR

A93056

Fig. 37—Concentric Vent and Combustion-Air Roof

Termination (Dimension "A" is Touching or

2-In. Maximum Separation)

VENT

1″ MAXIMUM (TYP)

COMBUSTION AIR

VENT

A93057

Fig. 38—Concentric Vent and Combustion-Air Side

Termination (Dimension "A" is Touching or

2-In. Maximum Separation)

VENT

COMBUSTION AIR

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

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

Maximum Separation)

A96129

—30—

COMBUSTION AIR

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

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

Maximum Separation)

A96130

OPEN STAND

PIPE FOR

A/C OR

HUMIDIFIER

DRAIN

TEE

TO OPEN DRAIN

A94054

Fig. 41—Example of Field Drain Attachment

CONDENSATE TRAP

WIRE TIE(S)

(3 WRAPS MINIMUM)

HEAT TAPE

Fig. 42—Condensate Trap Heat Tape

A93036

SEQUENCE OF OPERATION

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.

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.

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.

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.

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.

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.

2. Humidifier (HUM)—The HUM terminal is energized after the inducer prepurge period is completed.

3. Ignitor warm up—At end of prepurge period, the hot surface ignitor (HSI) is energized for a 17-sec HSI warm-up period.

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.

NOTE: The initial heat mode after 115-v or 24-v power interruption 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 lowand 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.

5. Flame sensing—When burner flame is sensed, the control center holds gas valve open and begins blower on delay period.

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.

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.

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.

8. Electronic Air Cleaner—The EAC-1 terminal is energized whenever the blower operates.

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—

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.

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

after gas valve is de-energized.

III. HEATING MODE—TWO STAGE

The control center provides 2-stage heating using a single-stage thermostat. The control center maximizes comfort while optimizing efficiency to meet the demands of conditioned area when a thermostat R-W/W1 signal is received.

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.

NOTE: When using 2-stage thermostat operation with R-W/W1 and R-W2 signals, setup switch SW-2 MUST be in ON position.

The heat cycle operates as stated in Heating Mode section. 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 recommended to provide heat until replacement components can be obtained or fault resolved.

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: No safeties are bypassed when using emergency heat mode.

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.

In emergency heat mode, the normal heat mode outlined in Heating Mode section is not followed. The following sequence will occur:

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

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 highpressure switch closes.

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.

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

operate in emergency heat mode.

4. Humidifier—The HUM terminal is energized IMMEDI-

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: 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.

NOTE: Ignition sequence repeats 3 additional times before 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. Fault codes will not flash in emergency heat mode.

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.

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

stops immediately.

V. COOLING MODE A. Single-Speed Applications

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

1. Cooling unit—The cooling unit starts when thermostat

R-Y signal is received.

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.

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.)

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.

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

whenever blower operates.

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

signal is terminated.

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

R-Y/Y2 and R-G signals are terminated, and blower remains operating for 90 sec.

B. Two-Speed Applications

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

VI. HEAT PUMP MODE A. Single-Speed Applications

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.

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.

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.

—32—

2-SPEED

THERMOSTAT

R R

C C

Y2 Y2

L L

Y1 Y1

VARIABLE

SPEED

THERMOSTAT

W/W1

Y/Y2

2-SPEED AIR

CONDITIONER

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

The blower continues to operate completing a normal blower off delay.

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.

2-SPEED

THERMOSTAT

R R

C C

Y2 Y2

VARIABLE

SPEED

THERMOSTAT

W/W1

Y/Y2

2-SPEED

HEAT PUMP

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.

5. 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.

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

the blower stops for 25 sec to allow heat exchangers to warm up.

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

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

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.

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.

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

still present—The blower changes its speed to cooling RPM.

L L

O O

Y1 Y1

A94303

Fig. 44—Wiring Schematic for 2-Speed

Heat Pump Applications

VII. CONTINUOUS FAN MODE

1. Operating with continuous fan only— a. Call for continuous fan—The thermostat closes R-G

circuit.

b. Blower on—The blower starts immediately.

NOTE: The continuous fan speed is the same as low-heat speed unless it is field adjusted to another desired airflow. See Continuous Fan Setup Switches section. There is also a chart on wiring diagram. (See Fig. 24.)

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

gized whenever blower operates, regardless of operating mode.

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.

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.

—33—

VIII. COMPONENT TEST

All components are functionally operated except gas valve with component test feature.

This feature helps diagnose a system problem in case of a component failure.

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.

3. Remove blower access panel.

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.

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.

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

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.

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 deenergized.

4. Main blower motor operates for 20 sec at low speed, operates for 20 sec at high speed, then turns off.

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.

NOTE: To repeat component test, turn setup switch SW-6 to OFF and then back to ON.

After component test, perform the following:

1. Release blower panel access door switch and turn setup switch SW-6 to OFF position.

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.

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 bypassed air supply.

X. DEHUMIDIFICATION MODE

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.

XI. ZONE MODE

When setup switch SW-5 MZ is in ON position, blower motor control is the same as above except with the following exceptions:

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.

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.

START-UP PROCEDURES

I. GENERAL

1. Furnace must have a 115-v power supply properly connected and grounded.

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.

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).

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.

Before operating furnace, check each manual reset switch for continuity. If necessary, press button to reset switch.

II. SELECT SETUP SWITCH POSITIONS A. Air Conditioning (A/C) Setup Switches

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.

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.

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.

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.

B. Continuous Fan (CF) Setup Switches

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—

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

AIR

CONDITIONER

(TONS) Default

1-1/2 600 ON OFF OFF X X X — — —

2 800OFFONOFFXXXXXX

2-1/2 1000 ON ON OFF XXXXXX

3 1200 OFF OFF ON XXXXXX

3-1/2 1400 ON OFF ON XXXXXX

4 1600 OFF ON ON — — — X X X 5 2000 ON ON ON — — — X X X

X—Indicates allowable selection.

CFM AIRFLOW

1200 or

2000

A/C SETUP

SWITCH POSITION

A/C-1 A/C-2 A/C-3 042040 042060 042080 060080 060100 060120

OFF OFF OFF

3 Tons

1200 CFM

ALLOWABLE FURNACE MODEL SETUP

3 Tons

1200 CFM

3 Tons

1200 CFM

5 Tons

2000 CFM

5 Tons

2000 CFM

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

CONTINUOUS

FAN (CFM)

Default OFF OFF OFF 565* 515* 690* 690* 860* 1035*

600 ON OFF OFF X X X — — —

800 OFFONOFFXXXXXX 1000 ONONOFFXXXXXX 1200 OFFOFFONXXXXXX 1400 ONOFFONXXXXXX 1600 OFF ON ON — — — X X X 2000 ON ON ON — — — X X X

* Add 15% additional CFM when Bypass Humidifier switch SW-3 on control board is used. X—Indicates allowable selection.

CF-1 CF-2 CF-3 042040 042060 042080 060080 060100 060120

CF SETUP

SWITCH POSITION

ALLOWABLE FURNACE MODEL SETUP

5 Tons

OFF

A95198

Fig. 45—Example of Setup Switch in OFF Position

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.)

NOTE: The CF switches are factory set to provide continuous fan airflow equal to low-heat mode.

5. Replace main furnace door and blower access panel.

C. Setup Switches (SW)

The control center has 8 setup switches that may be set to meet the application requirements. Position these setup switches for the appropriate requirement.

1. Remove main furnace door and blower access panel.

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

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.

III. PRIME CONDENSATE TRAP WITH WATER

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 pouring water into the inducer drain side of condensate trap.

1. Remove upper inducer housing drain connection cap. (See Fig. 46.)

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

3. Insert field-supplied funnel into tube.

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.)

5. Remove funnel and tube from inducer housing and replace drain connection cap and clamp.

—35—

TABLE 10—SETUP SWITCH DESCRIPTION

SETUP

SWITCH NO.

SW-1 (FLT)

SW-2

(LOW)

SW-3

(BPH)

SW-4

(EMER HEAT)

SW-5

(MZ)

SW-6

(COMP TEST)

SW-7 and -8

(Blower Off Delay)

NORMAL

POSITION

OFF

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

OFF

See Table 11

TABLE 11—BLOWER OFF DELAY SETUP SWITCH

POSITION

DESIRED HEATING

MODE BLOWER

OFF DELAY (SEC)

90 OFF OFF 135 ON OFF 180 OFF ON 225 ON ON

SETUP SWITCH (SW-7 AND -8) POSITION

SW-7 SW-8

DESCRIPTION OF USE

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

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.

Turn switch to ON to bypass microprocessor control. Furnace will operate at high heat only with main blower and inducer motor operating at maximum RPM. NO safeties are bypassed.

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.

Turn switch to ON to initiate component test. Furnace will operate inducer 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.

Adjust switches to provide desired heating mode blower off delay time, 90, 135, 180, or 225 sec.

Fig. 46—Inducer Housing Drain Tube

A94208

A94209

Fig. 47—Filling Condensate Trap

—36—

IV. PURGE GAS LINES

If not previously done, purge the lines after all connections have been made and check for leaks.

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.

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.

1. Determine natural gas orifice size and manifold pressure for correct input. a. Obtain yearly heat value average (at installed altitude)

from local gas supplier.

b. Obtain yearly specific gravity average from local gas

supplier.

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

model 355MAV Furnaces.

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.

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.

EXAMPLE: (0—2000 ft altitude) Heating value = 1050 Btu/cu ft Specific gravity = 0.62 Therefore: Orifice No. 45

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. Check and verify burner orifice size in furnace. NEVER

ASSUME ORIFICE SIZE; ALWAYS CHECK AND VERIFY.

2. Adjust manifold pressure to obtain input rate. a. Remove burner enclosure front.

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.)

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

position. (See Fig. 25.) This keeps furnace locked in low-heat operation.

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

center to start furnace.

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

counterclockwise (out) to decrease input rate or clockwise (in) to increase input rate.

LOW-FIRE ADJUSTMENT ALLEN SCREW (UNDER CAP)

HIGH-FIRE ADJUSTMENT ALLEN SCREW (UNDER CAP)

→

ON/OFF SWITCH

INLET PRESSURE TAP

BURNER ENCLOSURE REFERENCE

PRESSURE TAP

O

F

MANIFOLD

PRESSURE

TAP

Fig. 48—Redundant Automatic Gas Valve

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.

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.

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.

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

ing low-heat adjustment.

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 clockwise (in) to increase rate.

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.

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.)

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.

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

UNITED STATES

A97386

—37—

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)

ALTITUDE

RANGE

(FT)

0 925 44 3.5/1.5 44 3.7/1.6 44 3.8/1.6 43 3.4/1.4 43 3.5/1.5

to 975 44 3.2/1.3 44 3.3/1.4 44 3.4/1.4 44 3.5/1.5 44 3.6/1.5

2000 1025 45 3.5/1.5 45 3.6/1.5 45 3.7/1.6 44 3.2/1.3 44 3.3/1.4

U.S.A. and Canada

ALTITUDE

RANGE

(FT)

U.S.A. 775 43 3.8/1.6 42 3.2/1.4 42 3.3/1.4 42 3.4/1.4 42 3.5/1.5

Altitudes 800 43 3.5/1.5 43 3.7/1.5 43 3.8/1.6 42 3.2/1.4 42 3.3/1.4

2001 825 44 3.8/1.6 43 3.4/1.5 43 3.6/1.5 43 3.7/1.5 43 3.8/1.6

to 850 44 3.6/1.5 44 3.7/1.6 44 3.8/1.6 43 3.5/1.5 43 3.6/1.5

3000 875 44 3.4/1.4 44 3.5/1.5 44 3.6/1.5 44 3.7/1.6 43 3.4/1.4

or 900 44 3.2/1.4 44 3.3/1.4 44 3.4/1.4 44 3.5/1.5 44 3.6/1.5

Canada 925 45 3.7/1.5 45 3.8/1.6 44 3.2/1.4 44 3.3/1.4 44 3.4/1.5

Altitudes 950 45 3.5/1.5 45 3.6/1.5 45 3.7/1.6 45 3.8/1.6 44 3.3/1.4

U.S.A. and Canada

2000 975 45 3.3/1.4 45 3.4/1.4 45 3.5/1.5 45 3.6/1.5 45 3.8/1.6

to 1000 47 3.7/1.6 45 3.2/1.4 45 3.4/1.4 45 3.5/1.5 45 3.6/1.5

4500 1025 47 3.6/1.5 47 3.7/1.6 45 3.2/1.3 45 3.3/1.4 45 3.4/1.4

ALTITUDE

RANGE

(FT)

3001 825 44 3.5/1.5 44 3.6/1.5 44 3.8/1.6 43 3.4/1.4 43 3.5/1.5

to 875 45 3.8/1.6 44 3.2/1.4 44 3.3/1.4 44 3.5/1.5 44 3.6/1.5

U.S.A. Only

4000 925 45 3.4/1.4 45 3.5/1.5 45 3.6/1.5 45 3.7/1.6 44 3.2/1.3

AVG GAS HEAT VALUE AT ALTITUDE

(BTU/CU FT)

850 43 3.7/1.5 43 3.8/1.6 42 3.2/1.4 42 3.3/1.4 42 3.4/1.4 875 43 3.5/1.5 43 3.6/1.5 43 3.7/1.6 43 3.8/1.6 42 3.2/1.4 900 44 3.7/1.6 43 3.4/1.4 43 3.5/1.5 43 3.6/1.5 43 3.7/1.6

950 44 3.4/1.4 44 3.5/1.5 44 3.6/1.5 44 3.7/1.6 44 3.8/1.6

1000 45 3.7/1.6 45 3.8/1.6 44 3.2/1.4 44 3.4/1.4 44 3.5/1.5

1050 45 3.3/1.4 45 3.4/1.5 45 3.6/1.5 45 3.7/1.6 45 3.8/1.6 1075 45 3.2/1.3 45 3.3/1.4 45 3.4/1.4 45 3.5/1.5 45 3.6/1.5 1100 47 3.6/1.5 47 3.7/1.6 45 3.2/1.4 45 3.4/1.4 45 3.5/1.5

AVG GAS HEAT VALUE AT ALTITUDE

(BTU/CU FT)

AVG GAS HEAT VALUE AT ALTITUDE

(BTU/CU FT)

750 43 3.7/1.6 43 3.8/1.6 42 3.3/1.4 42 3.4/1.4 42 3.5/1.5 775 43 3.5/1.5 43 3.6/1.5 43 3.7/1.6 43 3.8/1.6 42 3.2/1.4 800 44 3.7/1.6 43 3.4/1.4 43 3.5/1.5 43 3.6/1.5 43 3.7/1.6

850 44 3.3/1.4 44 3.4/1.4 44 3.5/1.5 44 3.7/1.5 44 3.8/1.6

900 45 3.6/1.5 45 3.7/1.6 45 3.8/1.6 44 3.3/1.4 44 3.4/1.4

950 45 3.2/1.4 45 3.3/1.4 45 3.4/1.5 45 3.5/1.5 45 3.7/1.5 975 47 3.6/1.5 45 3.2/1.3 45 3.3/1.4 45 3.4/1.4 45 3.5/1.5

1000 47 3.5/1.5 47 3.6/1.5 47 3.7/1.6 45 3.2/1.4 45 3.3/1.4

0.58 0.60 0.62 0.64 0.66

Orifice

No.

Orifice

No.

Orifice

No.

Manifold

Pressure

High/Low

0.58 0.60 0.62 0.64 0.66

Manifold

Pressure

High/Low

0.58 0.60 0.62 0.64 0.66

Manifold

Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

SPECIFIC GRAVITY OF NATURAL GAS

Manifold Pressure High/Low

SPECIFIC GRAVITY OF NATURAL GAS

Manifold Pressure High/Low

SPECIFIC GRAVITY OF NATURAL GAS

Manifold Pressure High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Manifold Pressure

High/Low

Manifold Pressure

High/Low

Manifold Pressure

High/Low

—38—

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)

ALTITUDE

RANGE

(FT)

4001 800 44 3.5/1.5 44 3.6/1.5 44 3.7/1.6 44 3.8/1.6 43 3.4/1.4

to 850 45 3.7/1.6 45 3.8/1.6 44 3.3/1.4 44 3.4/1.4 44 3.5/1.5

U.S.A. Only

5000 900 45 3.3/1.4 45 3.4/1.4 45 3.5/1.5 45 3.6/1.5 45 3.8/1.6

ALTITUDE

RANGE

(FT)

5001 800 44 3.2/1.3 44 3.3/1.4 44 3.4/1.4 44 3.5/1.5 44 3.6/1.5

to 850 45 3.4/1.4 45 3.5/1.5 45 3.6/1.5 45 3.8/1.6 44 3.2/1.4

U.S.A. Only

6000 900 47 3.6/1.5 47 3.7/1.6 45 3.3/1.4 45 3.4/1.4 45 3.5/1.5

ALTITUDE

RANGE

(FT)

6001 725 44 3.6/1.5 44 3.7/1.6 44 3.8/1.6 43 3.4/1.4 43 3.5/1.5

to 775 45 3.8/1.6 44 3.2/1.4 44 3.3/1.4 44 3.4/1.5 44 3.5/1.5

U.S.A. Only

7000 825 45 3.3/1.4 45 3.4/1.5 45 3.6/1.5 45 3.7/1.6 45 3.8/1.6

AVG GAS

HEAT VALUE

AT ALTITUDE

(BTU/CU FT)

725 43 3.7/1.5 43 3.8/1.6 42 3.2/1.4 42 3.3/1.4 42 3.4/1.4 750 43 3.4/1.4 43 3.5/1.5 43 3.7/1.5 43 3.8/1.6 42 3.2/1.4 775 44 3.7/1.6 44 3.8/1.6 43 3.4/1.4 43 3.5/1.5 43 3.7/1.5

825 44 3.2/1.4 44 3.4/1.4 44 3.5/1.5 44 3.6/1.5 44 3.7/1.6

875 45 3.5/1.5 45 3.6/1.5 45 3.7/1.6 44 3.2/1.3 44 3.3/1.4

925 47 3.7/1.6 45 3.2/1.4 45 3.3/1.4 45 3.4/1.5 45 3.6/1.5 950 47 3.5/1.5 47 3.6/1.5 45 3.2/1.3 45 3.3/1.4 45 3.4/1.4

AVG GAS

HEAT VALUE

AT ALTITUDE

(BTU/CU FT)

700 43 3.6/1.5 43 3.7/1.6 42 3.2/1.3 42 3.3/1.4 42 3.4/1.4 725 43 3.4/1.4 43 3.5/1.5 43 3.6/1.5 43 3.7/1.6 43 3.8/1.6 750 44 3.6/1.5 44 3.7/1.6 43 3.4/1.4 43 3.5/1.5 43 3.6/1.5 775 44 3.4/1.4 44 3.5/1.5 44 3.6/1.5 44 3.7/1.6 43 3.4/1.4

825 45 3.6/1.5 45 3.7/1.6 44 3.2/1.4 44 3.3/1.4 44 3.4/1.4

875 45 3.2/1.4 45 3.3/1.4 45 3.4/1.5 45 3.6/1.5 45 3.7/1.5

925 47 3.4/1.4 47 3.5/1.5 47 3.7/1.5 45 3.2/1.3 45 3.3/1.4 950 48 3.7/1.6 48 3.8/1.6 47 3.5/1.5 47 3.6/1.5 47 3.7/1.6 975 48 3.5/1.5 48 3.6/1.5 48 3.8/1.6 47 3.4/1.4 47 3.5/1.5

1000 48 3.3/1.4 48 3.5/1.5 48 3.6/1.5 48 3.7/1.6 48 3.8/1.6

AVG GAS

HEAT VALUE

AT ALTITUDE

(BTU/CU FT)

650 42 3.2/1.3 42 3.3/1.4 42 3.4/1.4 42 3.5/1.5 42 3.6/1.5 675 43 3.6/1.5 43 3.7/1.6 43 3.8/1.6 42 3.2/1.4 42 3.3/1.4 700 44 3.8/1.6 43 3.4/1.5 43 3.6/1.5 43 3.7/1.6 43 3.8/1.6

750 44 3.3/1.4 44 3.4/1.5 44 3.6/1.5 44 3.7/1.6 44 3.8/1.6

800 45 3.5/1.5 45 3.7/1.5 45 3.8/1.6 44 3.2/1.4 44 3.3/1.4

850 47 3.7/1.6 45 3.2/1.4 45 3.4/1.4 45 3.5/1.5 45 3.6/1.5 875 47 3.5/1.5 47 3.6/1.5 45 3.2/1.3 45 3.3/1.4 45 3.4/1.4

0.58 0.60 0.62 0.64 0.66

Orifice

No.

Orifice

No.

Orifice

No.

Manifold Pressure High/Low

0.58 0.60 0.62 0.64 0.66

Manifold Pressure High/Low

0.58 0.60 0.62 0.64 0.66

Manifold Pressure High/Low

Orifice

No.

Orifice

No.

Orifice

No.

SPECIFIC GRAVITY OF NATURAL GAS

No.

Manifold Pressure

High/Low

Manifold Pressure

High/Low

Manifold Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Manifold Pressure High/Low

SPECIFIC GRAVITY OF NATURAL GAS

Manifold Pressure High/Low

SPECIFIC GRAVITY OF NATURAL GAS

Manifold Pressure High/Low

Orifice

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Manifold Pressure

High/Low

Manifold Pressure High/Low

—39—

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)

ALTITUDE

RANGE

(FT)

7001 700 44 3.5/1.5 44 3.6/1.5 44 3.8/1.6 43 3.4/1.4 43 3.5/1.5

to 750 45 3.7/1.6 45 3.8/1.6 44 3.3/1.4 44 3.4/1.4 44 3.5/1.5

U.S.A. Only

8000 800 45 3.3/1.4 45 3.4/1.4 45 3.5/1.5 45 3.6/1.5 45 3.7/1.6

ALTITUDE

RANGE

(FT)

8001 650 44 3.7/1.6 43 3.4/1.4 43 3.5/1.5 43 3.6/1.5 43 3.7/1.6

to 700 44 3.2/1.4 44 3.3/1.4 44 3.4/1.5 44 3.6/1.5 44 3.7/1.6

U.S.A. Only

9000 750 45 3.4/1.4 45 3.5/1.5 45 3.6/1.5 45 3.8/1.6 44 3.2/1.4

ALTITUDE

RANGE

(FT)

9001 625 44 3.7/1.6 44 3.8/1.6 43 3.5/1.5 43 3.6/1.5 43 3.7/1.6

to 675 45 3.8/1.6 44 3.3/1.4 44 3.4/1.4 44 3.5/1.5 44 3.6/1.5

U.S.A. Only

10,000 725 45 3.3/1.4 45 3.4/1.5 45 3.6/1.5 45 3.7/1.6 45 3.8/1.6

AVG GAS HEAT VALUE AT ALTITUDE

(BTU/CU FT)

625 43 3.8/1.6 42 3.3/1.4 42 3.4/1.4 42 3.5/1.5 42 3.6/1.5 650 43 3.5/1.5 43 3.7/1.6 43 3.8/1.6 42 3.2/1.4 42 3.3/1.4 675 44 3.8/1.6 43 3.4/1.4 43 3.5/1.5 43 3.6/1.5 43 3.7/1.6

725 44 3.3/1.4 44 3.4/1.4 44 3.5/1.5 44 3.6/1.5 44 3.7/1.6

775 45 3.5/1.5 45 3.6/1.5 45 3.7/1.6 45 3.8/1.6 44 3.3/1.4

825 47 3.6/1.5 45 3.2/1.3 45 3.3/1.4 45 3.4/1.4 45 3.5/1.5 850 47 3.4/1.4 47 3.5/1.5 47 3.7/1.5 45 3.2/1.3 45 3.3/1.4

AVG GAS HEAT VALUE AT ALTITUDE

(BTU/CU FT)

600 43 3.8/1.6 42 3.3/1.4 42 3.4/1.4 42 3.5/1.5 42 3.6/1.5 625 43 3.5/1.5 43 3.6/1.5 43 3.8/1.6 42 3.2/1.4 42 3.3/1.4

675 44 3.5/1.5 44 3.6/1.5 44 3.7/1.6 44 3.8/1.6 43 3.4/1.5

725 45 3.6/1.5 45 3.8/1.6 44 3.2/1.4 44 3.3/1.4 44 3.4/1.4

775 45 3.2/1.3 45 3.3/1.4 45 3.4/1.4 45 3.5/1.5 45 3.6/1.5 800 47 3.6/1.5 47 3.7/1.6 45 3.2/1.3 45 3.3/1.4 45 3.4/1.4

AVG GAS HEAT VALUE AT ALTITUDE

(BTU/CU FT)

575 43 3.8/1.6 42 3.2/1.4 42 3.3/1.4 42 3.5/1.5 42 3.6/1.5 600 43 3.5/1.5 43 3.6/1.5 43 3.7/1.6 42 3.2/1.3 42 3.3/1.4

650 44 3.4/1.4 44 3.5/1.5 44 3.7/1.5 44 3.8/1.6 43 3.4/1.4

700 45 3.6/1.5 45 3.7/1.6 45 3.8/1.6 44 3.3/1.4 44 3.4/1.4

750 47 3.7/1.6 45 3.2/1.4 45 3.3/1.4 45 3.4/1.5 45 3.5/1.5 775 47 3.5/1.5 47 3.6/1.5 47 3.7/1.6 45 3.2/1.4 45 3.3/1.4

0.58 0.60 0.62 0.64 0.66

Orifice

No.

Orifice

No.

Orifice

No.

Manifold

Pressure

High/Low

0.58 0.60 0.62 0.64 0.66

Manifold

Pressure

High/Low

0.58 0.60 0.62 0.64 0.66

Manifold

Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

SPECIFIC GRAVITY OF NATURAL GAS

Manifold Pressure High/Low

SPECIFIC GRAVITY OF NATURAL GAS

Manifold Pressure High/Low

SPECIFIC GRAVITY OF NATURAL GAS

Manifold Pressure High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Manifold

Pressure

High/Low

Orifice

No.

Orifice

No.

Orifice

No.

Manifold Pressure

High/Low

Manifold Pressure

High/Low

Manifold Pressure

High/Low

—40—

BURNER 

ORIFICE

EXAMPLE: 100,000 Btuh input furnace installed at 4300 ft.

Furnace Input

Rate at

Sea Level

100,000 X 0.91 = 91,000

Multiplier

Derate

Factor

Furnace Input Rate

at Installation

Altitude

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.

A93059

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 exchangers, causing failures.

BURNER FLAME

BURNER

MANIFOLD

A89020

Fig. 49—Burner Flame

b. Reinstall burner box cover.

NOTE: Clocking gas input rate MUST always be performed with the burner box cover INSTALLED.

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.

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). 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.

At altitudes above 2000 ft, this furnace has been approved for a 2 percent derate for each 1000 ft above sea level. See Table 13 for derate multiplier factor and example.

TABLE 13—ALTITUDE DERATE MULTIPLIER FOR U.S.A.

ALTITUDE

(FT)

0—2000 0 1.00 2001—3000 4—6 0.95 3001—4000 6—8 0.93 4001—5000 8—10 0.91 5001—6000 10—12 0.89 6001—7000 12—14 0.87 7001—8000 14—16 0.85 8001—9000 16—18 0.83

9001—10,000 18—20 0.81

* Derate multiplier factor is based on midpoint altitude for altitude range.

%OF

DERATE

DERATE MULTIPLIER FACTOR FOR U.S.A.*

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.

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.

m. Remove jumper across R, W/W1, and W2 thermostat

connections to terminate call for heat.

—41—

TABLE 14—GAS RATE CU FT/HR

SECONDS

FOR 1

REVOLUTION

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49

SIZE OF TEST DIAL

1 cu ft2cu ft5cu ft 360

720 655 600 555 514 480 450 424 400 379 360 343 327 313 300 288 277 267 257 248 240 232 225 218 212 206 200 195 189 185 180 176 172 167 164 160 157 153 150 147

1800 1636 1500 1385 1286 1200 1125 1059 1000

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

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

97 95 92 90 88 86 84 82 80 78 76 75 73

B. Set Temperature Rise

SECONDS

FOR 1

REVOLUTION

50 51 52 53 54 55 56 57 58 59 60 62 64 66 68 70 72 74 76 78 80 82 84 86 88 90 92 94 96

98 100 102 104 106 108

110 112 116 120

SIZE OF TEST DIAL

cu ft2cu ft5cu ft

144 141 138 136 133 131 129 126 124 122 120 116 112 109 106 103 100

97 95 92 90 88 86 84 82 80 78 76 75 74 72 71 69 68 67

65 64 62 60

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

164 161 155 150

71 69 68 67 65 64 63 62 61 60 58 56 54 53 51 50 48 47 46 45 44 43 42 41 40 39 38 38 37 36 35 35 34 33

33 32 31 30

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.)

e. Check Troubleshooting Guide for Variable-Speed

2-Stage Electronic Condensing Furnaces.

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.

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

R Y W G

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 exchangers.

Furnace must operate within range of temperature rise specified on the unit rating plate. Determine air temperature rise as follows:

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.

2. When thermometer readings stabilize, subtract return-air temperature from supply-air temperature to determine air temperature rise.

NOTE: Temperature rise can be determined for low-fire operation 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.)

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:

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.

10 TURNS

FROM UNIT 24-V CONTROL TERMINALS

EXAMPLE:

5.0 AMPS ON AMMETER 10 TURNS AROUND JAWS

0.5 AMPS FOR THERMOSTAT

ANTICIPATOR SETTING

A96316

Fig. 50—Amp Draw Check with Ammeter

CHECK SAFETY CONTROLS

I. CHECK PRIMARY LIMIT CONTROL

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. 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.

—42—

II. CHECK PRESSURE SWITCHES

This control proves operation of the draft inducer. Check switch operation as follows:

1. Turn off 115-v power to furnace.

2. Remove control access door and disconnect inducer motor 12-pin wire harness at inducer motor.

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.

5. Turn off 115-v power to furnace.

6. Reconnect inducer motor wire harness. Reinstall furnace access door.

7. Turn on 115-v power to furnace.

8. Reset thermostat to desired temperature.

CHECKLIST

1. Put away tools and instruments. Clean up debris.

2. Verify manual reset switch has continuity.

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 instructions.

6. Review User’s Manual with owner.

7. Leave literature packet near furnace.

—43—

LOAD CALCULATION

____________ Heating Load (Btuh)

____________ Cooling Load (Btuh)

____________ Furnace Model Selection

CHECKLIST—INSTALLATION

________ Unit Level or Pitched Forward

________

Condensate Drain

Internal Tubing Connections Free of Kinks and Traps

COMBUSTION AND VENT PIPING

Termination Location

________ Roof or Sidewall

________ Termination Kit — 2 Pipe or Concentric

________ Combustion-Air Pipe Length

________ Combustion-Air Pipe Elbow Quantity

________ Vent Pipe Length

________ Vent Pipe Elbow Quantity

________ Pipe Diameter Determined from Sizing Table

________ Pipe Sloped To Furnace

Pipe Insulation

________ Over Ceilings

________ Low-Ambient Exposed Pipes

________

________ Condensate Trap Primed before Start-Up

________ Heat Tape Installed if Required

________

________ Temperature Rise Adjusted

________ Anticipator Setting Adjusted or

________ Cycle Rate (3 Cycles per Hr) Selected

________ Primary Limit

________ Pressure Switches

External Drain Connection Leak Tight and Sloped

CHECKLIST—START-UP

Gas Input Rate (Set Within 2 percent of Rating Plate)

Thermostat Anticipator

Safety Controls Check Operation

SERVICE TRAINING

Packaged Service Training programs are an excellent way to increase your knowledge of the equipment discussed in this manual, including:  • Unit Familiarization • Maintenance  • Installation Overview • 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

—44—

Printed in U.S.A. 355m405 Catalog No. BDP-5335-500

Bryant BRYANT 355M-40-5, 355MAV Installation And Operating Instructions Manual

Specifications and Main Features

Frequently Asked Questions

User Manual