Bryant GAMA 331JAV Installation And Operating Instructions Manual

installation, start-up,
and operating instructions

DOWNFLOW 2-SPEED,
2-STAGE, INDUCED-COMBUSTION
GAS-FIRED FURNACE

NOTE: Read the entire instruction manual before starting the
installation.
This symbol → indicates a change since the last issue.
Index Page

SAFETY CONSIDERATIONS .....................................................1

ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS

PROCEDURE........................................................................1-2

INTRODUCTION.......................................................................2-3

Dimensional Drawing ...............................................................2

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

LOCATION....................................................................................4

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

Location Relative to Cooling Equipment ................................4

Hazardous Locations.................................................................4

AIR FOR COMBUSTION AND VENTILATION...................4-5

Unconfined Space .....................................................................4

Confined Space......................................................................4-5

SUPPLY-AIR PLENUM INSTALLATION

(DOWNFLOW) .....................................................................5-6

Downflow Installation .............................................................5

Installation On Combustible Floor........................................5-6

FILTER ARRANGEMENT .......................................................6-7

GAS PIPING...............................................................................6-8

ELECTRICAL CONNECTIONS...............................................8-9

115-v Wiring.............................................................................8

24-v Wiring............................................................................8-9

Accessories .............................................................................. 9

VENTING ......................................................................................9

START-UP, ADJUSTMENT, AND SAFETY CHECK.......10-20

General ....................................................................................10

Sequence of Operation ......................................................10-14

Adaptive Heating Mode ....................................................10-12

Non-Adaptive Heating Mode .................................................12

Cooling Mode .........................................................................13

Continuous Blower Mode.......................................................13

Heat Pump Mode...............................................................13-14

Defrost Mode ..........................................................................14

Start-Up Procedures................................................................14

Adjustments .......................................................................14-20

Set Gas Input Rate ............................................................14-19

Set Temperature Rise ........................................................19-20

Set Thermostat Heat Anticipator............................................20

Check Safety Controls.......................................................20-21

Checklist..................................................................................21

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 the literature, on tags,
and on labels attached to or shipped with the unit and other safety
precautions that may apply.

331JAV

Series B

Cancels: II 331J-60-1 II 331J-60-2

12-97

ama

CANADIAN GAS ASSOCIATION

®

REGISTERED QUALITY SYSTEM

Follow all safety codes. In the United States, refer to the National
Fuel Gas Code (NFGC) NFPA No. 54-1996/ANSI Z223.1-1996.
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 the unit and in instructions or
manuals, be alert to the potential for personal injury.

Understand the signal words DANGER, WARNING, and CAU­TION. These words are used with the 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.

These instructions cover minimum requirements 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 up with changing residen­tial construction practices. We require these instructions as a
minimum for a safe installation.

ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS

PROCEDURE

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.

APPROVED

R

.

—1—

1

28

⁄2″

20″

13

⁄16″

7

39

⁄8″

11

⁄16″

INLET

7

⁄8″ DIA

ACCESSORY

3

⁄4″ DIA HOLE

1

GAS ENTRY

OUTLET

19″

ADDITIONAL

NOTE:

LOCATED IN THE TOP PLATE
AND BOTTOM PLATE

7

⁄8″ DIA K.O. ARE

VENT CONNECTION

13

⁄16″

1

9

⁄8″

1

10

⁄4″

1

1

⁄16″

1

2

⁄8″

1

8

⁄4″

11

⁄16″

D

E

A

AIRFLOW

1

⁄2″ DIA

2″

3

4

⁄16″

15

2

⁄16″

1

16

⁄16″

5

13

⁄16″

1

10

11

⁄16″

DIMPLES TO DRILL HOLES
FOR HANGER BOLTS (4 PLACES)
IN HORIZONTAL POSITION

⁄4″

THERMOSTAT 
WIRE ENTRY

7

⁄8″ DIA

ACCESSORY

7

⁄8″ DIA HOLE

POWER ENTRY

1

1

⁄2″ DIA

R.H. GAS ENTRY

7

⁄8″ DIA

ACCESSORY

1

1

⁄16″

1

2

⁄8″

″ TYP

1

5

⁄8″ TYP

Fig. 1—Dimensional Drawing
TABLE 1—DIMENSIONS (IN.)

UNIT SIZE A D E VENT CONN SHIP. WT

036060 14-3/16 12-9/16 12-11/16 4 145
048080 17-1/2 15-7/8 16 4 154
060100 21 19-3/8 19-1/2 4 181

A88324

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
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 model 331JAV Series B Furnace is available in sizes 60,000
through 100,000 Btuh input capacities.

The design of the downflow gas-fired furnace is A.G.A./C.G.A.
certified for natural and propane gases and for installation on
noncombustible flooring. The furnace is factory-shipped for use
with natural gas. The manufacturer’s accessory 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, the manufacturer’s 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. This furnace is for installation
in alcoves, attics, crawlspaces, basements, closets, or utility rooms.
The design of this furnace line is not A.G.A./C.G.A. certified for
installation in mobile homes, recreation vehicles, or outdoors.

Before installing the furnace, refer to the current edition of the
NFGC and the NFPA 90B. Canadian installations must be installed
in accordance NSCNGPIC and all authorities having jurisdiction.
For a copy of the NFGC NFPA54/Z223.1, contact International
Approval Services U.S. Inc., 8501 E. Pleasant Valley Road,
Cleveland, OH 44131 or National Fire Protection Association Inc.,
Batterymarch Park, Quincy, MA 02269. For a copy of NFPA 90B,
contact National Fire Protection Association Inc., Batterymarch
Park, Quincy, MA 02269.

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.

The duct system should be designed and sized according to
accepted national standards published by: Air Conditioning Con­tractors Association (ACCA), Sheet Metal and Air Conditioning
Contractors National Association (SMACNA). Or consult the
Residential Systems Design Guidelines reference tables available
from your local distributor. The duct system should be sized to
handle the maximum CFM capabilities of the equipment at the
optimum design static pressure.

—2—

INSTALLATION

This unit is certified for downflow installation only. See Installation Manual for

important installation instructions.

MINIMUM INCHES CLEARANCE TO COMBUSTIBLE CONSTRUCTION

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

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 on
combustible flooring in alcove or closet at
minimum clearance from combustible
material.

This furnace may be used with a Type
B-1 Vent and may be vented in common
with other gas-fired appliances.

For installation on non-combustible

†

floors only. For installation on
combustible flooring only when
installed on special base, Part No.
KGASB0201ALL, Coil Assembly,
Part No. CD5 or CK5, or Coil
Casing, Part No. KCAKC.

For furnaces wider than 14.25

#

inches (362mm) may be 0 inches.

Ø

18 inches front clearance required

for alcove.

For single wall vent type 6 inches.

##

This furnace is approved for DOWNFLOW installations only.

1"

0"

B

A

C

K

E

D

I

S

1" #

Clearance in inches.

TOP / PLENUM

E

C

A

N

R

U

F

T

N

O

R

F

F

R

O

N

T

##

BOTTOM

†

"

1

Vent Clearance to combustibles:

For Single Wall vents 6 inches (6 po).
For Type B-1 vent type 1 inch (1 po).

#

1"

E

D

I

S

S

E

R

V

I

C

E

30"

MIN

Ø

322567-101 REV. E (LIT)

→

Fig. 2—Clearances to Combustibles

CAUTION: Application of this furnace should be in-

doors with special attention given to vent sizing and
material, gas input rate, air temperature rise, and unit
sizing. Improper installation or misapplication of the
furnace can require excessive servicing or cause prema­ture component failure.

Installation must conform to regulations of serving gas supplier
and local building, heating, and plumbing codes in effect in the
area in which installation is made, or in absence of local codes with
requirements of the NFGC.

This furnace is designed for a minimum continuous return-air
temperature of 60°F db or intermittent operation down to 55°F
such as when used with a night setback thermostat. Return-air
temperature must not exceed 85°F db.

To aid in installation, troubleshooting, and service, a status code
label is located on blower component door. This label explains
how to use the LED status indicated on furnace control which is
viewed through the sight glass on door.

A97620

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, loss of
life, 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. A
failure to follow this warning could result in electrical
shock, fire, personal injury, or death.

For high-altitude installation, the high-altitude conversion kit must
be installed at or above 5500 ft above sea level.

For accessory installation details, refer to applicable installation
literature.

NOTE: Remove all shipping brackets and materials before oper­ating furnace.

—3—

I. LOCATION

A. General

CAUTION: DO NOT install furnace in a corrosive or

contaminated atmosphere. Make sure all combustion and
circulating air requirements are followed.
DO NOT use this furnace during construction when
adhesives, sealers, and/or new carpets are being installed
and curing. If the furnace is required during construction,
use clean outside air for combustion and ventilation.
Compounds of chlorine and fluorine when burned in
combustion air form acids which will cause corrosion of
the heat exchangers and metal vent systems. Some of
these compounds are released from paneling and 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.

This furnace must be installed so electrical components are
protected from water.

Locate furnace as near to center of air distribution system and
chimney or vent as possible. The furnace should be installed as
level as possible.

When furnace is installed so that supply ducts carry air to areas
outside space containing furnace, the return air must also be
handled by a duct(s) sealed to furnace casing and terminating
outside space containing furnace.

Provide ample space for servicing and cleaning. Always comply
with minimum fire protection clearances shown on unit clearance
label. This furnace shall not be installed directly on carpeting, tile,
or any combustible material other than wood flooring. The furnace
may be installed on combustible flooring when installed with
accessory downflow subbase, which is available from your dis­tributor or branch when required.

B. Location Relative to Cooling Equipment

The cooling coil must be installed parallel with or on downstream
side of furnace to avoid condensation in heat exchangers. When
installed parallel with furnace, dampers or other means used to
control the flow of air must prevent chilled air from entering
furnace. If dampers are manually operated, they must be equipped
with means to prevent operation of either unit unless damper is in
full-heat or full-cooling position.

C. Hazardous Locations

When furnace is installed in a residential garage, it must be
installed so that burners and ignition source are at least 18 in.
above floor. The furnace should be protected from physical
damage by vehicles.

When furnace is installed in public garages, airplane hangars, or
other buildings having hazardous atmospheres, unit must be
installed in accordance with recommended good practice require­ments of the National Fire Protection Association, Inc.

II. AIR FOR COMBUSTION AND VENTILATION

Provisions for adequate combustion and ventilation air must be
provided in accordance with Section 5.3, Air for Combustion and
Ventilation, of the NFGC or applicable provisions of local building
codes.

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

CAUTION: Air for combustion must not be contami­nated by halogen compounds which include fluoride,
chloride, bromide, and iodide. These elements are found
in aerosol sprays, detergents, bleaches, cleaning solvents,
salts, air fresheners, and other household products.

CAUTION: The operation of exhaust fans, kitchen ven­tilation fans, clothes dryers, or fireplaces could create a
negative air pressure condition at the furnace. Make-up
air must be provided for these devices, in addition to that
required by the furnace.

All fuel-burning equipment must be supplied with air for combus­tion of the fuel. Sufficient air MUST be provided to ensure there
will not be a negative pressure in equipment room or space. In
addition, a positive seal MUST be made between furnace cabinet
and return-air duct to avoid pulling air from the burner area and
draft safeguard opening into circulating air.
The requirements for combustion and ventilation air depend upon
whether furnace is located in a CONFINED or UNCONFINED
space.

A. Unconfined Space

An unconfined space must have at least 50 cu ft for each 1000
Btuh of input for all appliances (such as furnaces, clothes dryer,
water heaters, etc.) in the space.
For Example:

331JAV FURNACE

HIGH-FIRE INPUT

BTUH
63,000 420
84,000 560

105,000 700

MINIMUM SQ FT

WITH

7-1/2 FT CEILING

If the unconfined space is constructed unusually tight, air for
combustion and ventilation MUST come from either the outdoors
or spaces freely communicating with outdoors. Combustion and
ventilation openings must be sized the same as for a confined
space as defined below. Return air must not be taken from the
room unless equal or greater amount of air is supplied to the room.

B. Confined Space

A confined space is defined as a space whose volume is less than
50 cu ft per 1000 Btuh of total input ratings of all appliances
installed in that space. A confined space MUST have provisions
for supplying air for combustion, ventilation, and dilution of flue
gases using 1 of the following methods.
NOTE: In determining free area of an opening, the blocking
effect of louvers, grilles, and screens must be considered. If free
area of louver or grille design is unknown, assume that wood
louvers have a 20 percent free area and metal louvers or grilles
have a 60 percent free area. Screens, when used, must not be
smaller than 1/4-in. mesh. Louvers and grilles must be constructed
so they cannot be closed.
The size of the openings depends upon whether air comes from
outside of the structure or an unconfined space inside the structure.

1. All air from an unconfined space inside the structure
requires 2 openings (for structures not usually tight):
a. Each opening MUST have at least 1 sq in. of free area

per 1000 Btuh of total input for all equipment within the
confined space, but not less than 100 sq in. per opening.
(See Fig. 3 and Table 2.) The minimum dimension of air
openings shall not be less than 3 in.

b. If the building is constructed unusually tight, a perma-

nent opening directly communicating with the outdoors
shall be provided. (See item 2 below.)

—4—

VENT THROUGH ROOF
(CATEGORY I)

DUCTS TO

OUTDOORS

1 SQ IN.
PER 4000
BTUH

*

RETURN

AIR

INTERIOR

HEATED

SPACE

SUPPLY AIR

* Minimum opening size is 100 sq in. with
minimum dimensions of 3 in.

†

Minimum of 3 in. when type B-1 vent is used.

12″ MAX

1 SQ IN.
PER 1000
BTUH* IN DOOR
OR WALL

UNCONFINED
SPACE

6″ MIN
(FRONT)

1 SQ IN.
PER 1000
BTUH* IN DOOR
OR WALL

†

12″ MAX

A93387

Fig. 3—Confined Space: Air for Combustion and Ventilation

from an Unconfined Space

c. If furnace is installed to obtain return air is taken directly

from hallway or space adjacent to furnace, all air for
combustion must come from outdoors.

2. Air from outside the structure requires 1 of the following
methods:

a. If combustion air is taken from outdoors through 2

vertical ducts, the openings and ducts MUST have at
least 1 sq in. of free area per 4000 Btuh of total input for
all equipment within the confined space. (See Fig. 4 and
Table 2.)

b. If combustion air is taken from outdoors through 2

horizontal ducts, the openings and ducts MUST have at
least 1 sq in. of free area per 2000 Btuh of total input for
all equipment within the confined space. (See Fig. 4 and
Table 2.)

c. If combustion air is taken from outdoors through a single

opening or duct (horizontal or vertical) commencing
within 12 in. of the top of the confined space, opening
and duct MUST have at least 1 sq in. of free area per
3000 Btuh of the total input for all equipment within the
confined space and not less than the sum of the areas of
all vent connectors in the confined space. (See Fig. 4 and
Table 2.) Equipment clearances to the structure shall be
at least 1 in. from the sides and back and 6 in. from the
front of the appliances.

When ducts are used, they must be of the same cross-sectional area
as the free area of the openings to which they connect. The
minimum dimension of ducts must not be less than 3 in. (See Fig.

4.)

12″ MAX

1 SQ IN.
PER 2000
BTUH

*

DUCTS

TO

OUTSIDE

1 SQ IN.
PER 2000
BTUH

*

12″ MAX

SUPPLY AIR

Minimum dimensions of 3 in.

*

NOTE:

Use any of the following
combinations of openings:
A & B C & D D & E F & G

RETURN

A

B

AIR

D

VENT
THROUGH
ROOF
(CATEGORY I)

CONFINED

C

DUCT

TO

OUTDOORS

F

SPACE

G

E

12″ MAX

12″

MAX

1 SQ IN.
PER 4000
BTUH

OUTDOORS

1 SQ IN.
PER 4000
BTUH

12″

MAX

1 SQ IN.
PER 4000
BTUH

*

*

A93388

Fig. 4—Confined Space: Air for Combustion and Ventilation

from Outdoors

III. SUPPLY-AIR PLENUM INSTALLATION (DOWN­FLOW)

A. Downflow Installation

→

NOTE: This furnace is approved for use on combustible flooring
when manufacturer’s accessory floor base Part No.
KGASB0201ALL is used. Manufacturer’s accessory floor base is
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.

1. Determine application being installed from Table 3.

2. Construct hole in floor per dimensions specified in Table 3
and Fig. 5.

3. Construct plenum to dimensions specified in Table 3.

4. If downflow subbase (KGASB) is used, install as shown in
Fig. 6.

If coil assembly CD5, CK5, or Coil Box KCAKC is used,
install as shown in Fig. 7.

B. Installation On Combustible Floor

1. Cut and frame hole in floor per dimensions in Installation
Instructions packaged with downflow subbase.

2. When completed, downflow subbase, plenum, and furnace
(or coil casing when used) should be installed as shown in
Fig. 6.

—5—

TABLE 2—FREE AREA OF COMBUSTION AIR OPENING

331JAV

FURNACE

HIGH-FIRE

INPUT

(BTUH)

63,000 100 15.8 5 31.5 7 21.0 6
84,000 100 21.0 6 42.0 8 28.0 6

105,000 105 26.3 6 52.5 9 35.0 7

AIR FROM

UNCONFINED

SPACE

Free Area

of Opening

(Sq In.)

OUTDOOR AIR THROUGH

VERTICAL DUCTS

Free Area of

Opening and Duct

(Sq In.)

(In. Dia)

Round

Pipe

OUTDOOR AIR THROUGH

HORIZONTAL DUCTS

Free Area of

Opening and Duct

(Sq In.)

(In. Dia)

Round

Pipe

OUTDOOR AIR THROUGH

SINGLE DUCT

Free Area of

Opening and Duct

(Sq In.)

A

PLENUM

OPENING

B

OPENING

D

FLOOR

C

Round

Pipe

(In. Dia)

Fig. 5—Floor and Plenum Opening Dimensions

TABLE 3—OPENING DIMENSIONS (IN.)

FURNACE

CASING

WIDTH

14-3/16

17-1/2

21

Combustible Flooring Using KGASB Subbase 11-13/16 19 13-7/16 20-3/8

Combustible Flooring with CD5 or CK5 Coil Assembly or

Combustible Flooring Using KGASB Subbase 15-1/8 19 16-3/4 20-3/8

Combustible Flooring with CD5 or CK5 Coil Assembly or

Combustible Flooring Using KGASB Subbase 18-5/8 19 20-1/4 20-3/8

Combustible Flooring with CD5 or CK5 Coil Assembly or

APPLICATION

Non-Combustible Flooring 12-11/16 19 13-3/8 19-5/8

KCAKC Coil Box

Non-Combustible Flooring 16 19 16-5/8 19-5/8

KCAKC Coil Box

Non-Combustible Flooring 19-1/2 19 20-1/8 19-5/8

KCAKC Coil Box

IV. FILTER ARRANGEMENT

WARNING: Never operate unit without a filter or with

filter access door removed. A failure to follow this
warning could result in fire, personal injury, or death.

The 2 factory-supplied filters are shipped in the blower compart­ment. After return-air duct has been connected to furnace, install
filters in a V-formation inside return-air plenum. (See Fig. 8.)

V. GAS PIPING

→

Gas piping must be installed in accordance with national and local
codes. Refer to the NFGC NFPA 54-1996/ANSI Z223.1-1996.
Canadian installations must be installed in accordance with NSC­NGPIC and all authorities having jurisdiction.

A96283

PLENUM OPENING FLOOR OPENING

ABCD

12-5/16 19 13-5/16 20

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

19 19 20 20

The gas supply line should be a separate line directly from the
meter to the furnace, if possible. Refer to Table 4 for recom­mended gas pipe sizing. Risers should be used to connect to the
furnace and to the meter.

CAUTION: If 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.

—6—

FURNACE

(OR COIL CASING

WHEN USED)

FURNACE

CD5 OR CK5

COIL ASSEMBLY

OR KCAKC

COIL BOX

COMBUSTIBLE

FLOORING

DOWNFLOW

SUBBASE

SHEET METAL

PLENUM

FLOOR

OPENING

A96285

Fig. 6—Furnace, Plenum, and Subbase Installed on

a Combustible Floor

WARNING: Use the proper length of pipes to avoid

stress on gas control manifold. A failure to follow this
warning could result in a gas leak causing fire, explosion,
personal injury, or death.

COMBUSTIBLE

FLOORING

SHEET METAL

PLENUM

FLOOR

OPENING

A96284

Fig. 7—Furnace, Plenum, and Coil Assembly or Coil Box

Installed on a Combustible Floor

CAUTION: Use a backup wrench at furnace gas control

when connecting gas pipe to furnace to avoid damaging
gas controls or manifold.

AIRFLOW

INSTALLATION

POSITION

OF FILTERS

RETURN-AIR

PLENUM

ACCESS DOOR

Fig. 8—Downflow Filter Arrangement

A88486

WARNING: Never purge a line into a combustion
chamber. Never use matches, candles, flame, or other
sources of ignition to check for gas leakage. Use a
soap-and-water solution to check for gas leaks. A failure
to follow this warning could result in fire, explosion,
personal injury, or death.

Piping should be pressure tested in accordance with local and
national plumbing and gas codes before furnace has been attached.
If test pressure exceeds 0.5 psig (14-in. wc), the 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 the gas valve before test.
It is recommended that ground joint union be loosened before
pressure testing.

Joint compounds (pipe dope) should be applied sparingly and only
to male threads of joints. This pipe dope must be resistant to action
of propane gas.

TABLE 4—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
supply line 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

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TABLE 5—ELECTRICAL DATA

UNIT
SIZE

VOLTS—
HERTZ—

PHASE

036060 115—60—1 127 104 10.5 14 35 15
048080 115—60—1 127 104 14.2 14 26 15
060100 115—60—1 127 104 17.9 12 32 20

* Permissible limits of the voltage range at which the unit will operate satisfactorily.
† Time-delay fuse is recommended.
‡ Length shown is as measured 1 way along wire path between unit and service panel for maximum 2 percent voltage drop.

Install accessible manual shutoff valve upstream of furnace gas
controls and within 72 in. of furnace. A 1/8-in. NPT plugged
tapping is provided on gas value for test gage connection.
Installation of additional 1/8-in. NPT plugged tapping, accessible
for test gage connection, installed immediately upstream of gas
supply connection to furnace and downstream of manual shutoff
valve is not required. Place ground joint union between gas control
manifold and manual shutoff.

Install sediment trap in riser leading to furnace. The trap can be
installed by connecting a tee to riser leading from furnace. Connect
capped nipple into lower end of tee. The capped nipple should
extend below level of gas controls. (See Fig. 9.)

OPERATING

VOLTAGE RANGE

Max* Min*

MAX

UNIT

AMPS

EAC - ELECTRONIC

(115-VAC 1 AMP MAX)

MIN

WIRE

GAGE

AIR CLEANER

MAX WIRE

LENGTH

78 9

456

123

FT‡

PR2

PR1

L2

L1

PARK

COM

EAC-1

EAC-2

-HEAT

-HEAT

HI-GAS

LO-GAS

HI-COOL

SEC-1

10 11 12

789

456

123

MASTER SLAVE

TWIN

TEST

1

After all connections have been made, purge lines and check for
gas leakage with regulated gas supply pressure.

1234

OFF

ON

MAX FUSE OR

HACR-TYPE

CKT BKR AMPS†

3-AMP

3

FU1

FUSE

LED -
DIAGNOSTIC

SEC-2

LIGHT

TWIN / TEST

LED

HUM
GRY/Y2W/W1

TERMINAL

HUM -
HUMIDIFIER
(24-VAC 0.5
AMP MAX)

1

24-VOLT
THERMOSTAT
TERMINALS

24 V

COM

W2

GAS

SUPPLY

MANUAL
SHUTOFF
VALVE
(REQUIRED)

SEDIMENT
TRAP

UNION

Fig. 9—Typical Gas Pipe Arrangement

VI. ELECTRICAL CONNECTIONS

A. 115-v Wiring

Refer to unit rating plate or Table 5 for equipment electrical
requirements. The control system requires an earth ground for
proper operation.

CAUTION: Do not connect aluminum wire between
disconnect switch and furnace. Use only copper wire.

Make all electrical connections in accordance with the current

→

edition of the National Electrical Code (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 CSA C22.1 Canadian Electrical Code or authori­ties having jurisdiction.

A89414

FURNACE AND
BLOWER OFF DELAY
SETUP SWITCHES

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

Fig. 10—Control Center

polarity is incorrect, the furnace control status LED will flash
rapidly and prevent heating operation.

→

WARNING: The cabinet must have an uninterrupted or
unbroken ground according to NEC ANSI/NFPA 70­1996 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.

B. 24-v Wiring

Refer to ESD Precautions Procedure before proceeding with 24-v
connections.
Make field 24-v connections at the 24-v terminal block. (See Fig.

10.) Connect terminal Y/Y2 as shown in Fig. 11 or 12 for proper
operation in cooling mode. Use AWG No. 18 color-coded, copper
thermostat wire only.
When furnace is installed in horizontal position with RH discharge
air, 24-v wire connections can be made easier by removing the 2
control box mounting screws and letting control box turn so that
24-v screw terminals are visible. Be sure to reinstall control box
after connections are made.
The 24-v circuit contains an automotive-type, 3-amp fuse located
on main control. Any 24-v electrical shorts during installation,
service, or maintenance could cause this fuse to blow. If fuse
replacement is required, use ONLY a 3-amp fuse. The control will
flash code 24 when fuse needs replacement.

C. Accessories

1. Electronic air cleaner (EAC)

A93348

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