Carrier 58TMA User Manual

Downflow/Horizontal 2-Speed, 2-Stage,

Induced-Combustion Gas Furnace

Visit www.carrier.com

Installation, Start-Up, and Operating Instructions

Sizes 065-125, Series 111

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 ...........................................................................2

INTRODUCTION.......................................................................2-4

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

Installation On Combustible Floor...........................................6

HORIZONTAL ATTIC INSTALLATION...................................7

HORIZONTAL CRAWLSPACE INSTALLATION....................7

FILTER ARRANGEMENT...........................................................7

GAS PIPING...............................................................................7-9

ELECTRICAL CONNECTIONS ................................................10

115-v Wiring...........................................................................10

24-v Wiring.............................................................................10

Accessories..............................................................................10

VENTING ....................................................................................10

START-UP, ADJUSTMENT, AND SAFETY CHECK.......10-22

General...............................................................................10-12

Sequence of Operation ......................................................12-16

Adaptive Heating Mode ....................................................12-14

Non-Adaptive Heating Mode .................................................14

Cooling Mode....................................................................14-15

Continuous Blower Mode.......................................................15

Heat Pump Mode....................................................................15

Defrost Mode.....................................................................15-16

Start-Up Procedures................................................................16

Adjustments .......................................................................16-22

Set Gas Input Rate ............................................................16-22

Set Temperature Rise ........................................................17-21

Set Thermostat Heat Anticipator ......................................21-22

Check Safety Controls............................................................22

Checklist..................................................................................23

®

CERTIFICATION OF
MANUFACTURING SITE

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.

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.

ama

58TMA

CANADIAN GAS ASSOCIATION

APPROVED

R

.

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Book 1 4
Tab 6a 8a

PC 101 Catalog No. 535-887 Printed in U.S.A. Form 58TMA-6SI Pg 1 8-97 Replaces: 58TMA-4SI

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

065-08 14-3/16 12-9/16 12-11/16 4 141
065-12 14-3/16 12-9/16 12-11/16 4 145
085-12 17-1/2 15-7/8 16 4 154
085-16 17-1/2 15-7/8 16 4 154
105-16 17-1/2 15-7/8 16 4 171
105-20 21 19-3/8 19-1/2 4 181
125-20 24-1/2 22-7/8 23 5 192

A88324

ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS

PROCEDURE

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
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 58TMA Series 111 Furnace is available in sizes 65,000
through 123,000 Btuh input capacities.

The design of the downflow/horizontal 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 factory­shipped 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

2

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.

#

18 inches front clearance required for alcove.

Ø

Indicates supply or return sides when furnace is in the horizontal

*

position. Line contact only permissible between lines formed by
intersections of the Top and two Sides of the furnace jacket, and
building joists, studs or framing.

For single wall vent type 6 inches.

##

For Type B-1 vent type 3 inches.

††

Clearance to Back 0 inches (0 po) in downflow and horizontal
(attic/alcove & crawlspace) positions and 3 inches (3 po) in
horizontal closet positions.

Clearance arrows do not change with furnace orientation.

1"

0"

††

B

A

C

K

E

D

I

S

1" #

*

Clearance in inches.

TOP / PLENUM

E

D

I

S

E

C

A

N

R

U

F

†

T

N

O

R

F

F

R

BOTTOM

#

"

1

S

E

R

V

I

O

N

T

##

Ø

Vent Clearance to combustibles:

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

1"

#

*

C

E

30"

MIN

322286-101 REV. D (LIT)

→

Fig. 2—Clearances to Combustibles

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.

A97430

Application of this furnace should be indoors 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.

3

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.

Step 1—Location

GENERAL

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.

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.

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.

Step 2—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.

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.

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.

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:

58TMA FURNACE
HIGH-FIRE INPUT

BTUH
63,000 420
84,000 560

105,000 700
123,000 820

MINIMUM SQ FT

WITH

7-1/2 FT CEILING

If 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.

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

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

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

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. (See Fig. 3 and Table 2.)

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 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 permanent

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

c. If furnace is installed on a raised platform to provide a

return-air plenum, and 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 hori-

zontal 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.)

Step 3—Supply-Air Plenum Installation (Downflow)

DOWNFLOW INSTALLATION

→

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

5

Table 2—Free Area Of Combustion Air Opening

58TMA

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
123,000 123 30.8 7 61.5 9 41.0 8

AIR UNCONFINED

SPACE FROM

Free Area

of Opening

(Sq In.)

OUTDOOR AIR THROUGH

VERTICAL DUCTS

Free Area of

Opening and Duct

(Sq In.)

Round

Pipe

(In. Dia)

OUTDOOR AIR THROUGH

HORIZONTAL DUCTS

Free Area of

Opening and Duct

(Sq In.)

Round

Pipe

(In. Dia)

OUTDOOR AIR THROUGH

SINGLE DUCT

Free Area of

Opening and Duct

(Sq In.)

Round

Pipe

(In. Dia)

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.

B

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.

INSTALLATION ON COMBUSTIBLE FLOOR

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

A

PLENUM

OPENING

D

FLOOR

OPENING

C

FURNACE

CASING

WIDTH

14-3/16

17-1/2

21

24-1/2

Fig. 5—Floor and Plenum Opening Dimensions

Table 3—Opening Dimensions (In.)

APPLICATION

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

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

Combustible Flooring with CD5 or CK5 Coil Assembly or

KCAKC Coil Box

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

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

Combustible Flooring with CD5 or CK5 Coil Assembly or

KCAKC Coil Box

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

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

Combustible Flooring with CD5 or CK5 Coil Assembly or

KCAKC Coil Box

Non-Combustible Flooring 23 19 23-5/8 19-5/8

Combustible Flooring Using KGASB Subbase 22-1/8 19 23-3/4 20-3/8

Combustible Flooring with CD5 or CK5 Coil Assembly or

KCAKC Coil Box

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

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

6

A96283

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

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

Combustible Floor

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

Step 4—Horizontal Attic Installation

Do not install furnace on its back; safety control operation
will be adversely affected. Never connect return-air ducts to
the sides or back of the furnace. A failure to follow this
warning could result in fire, personal injury, or death.

The furnace can be installed horizontally on either the left-hand
(LH) or right-hand (RH) side. A typical attic installation is shown
in Fig. 8.

CONSTRUCT WORKING PLATFORM

Construct working platform on location where all required furnace
clearances are met. (See Table 1 and Fig. 8.)

INSTALL FURNACE

1. Position furnace in desired location.

2. Connect gas supply pipe. See Fig. 8 for typical piping entry.

3. Connect supply- and return-air ducts.

4. Install field-supplied filter retainers as indicated in Fig. 11 and
Table 4 before connecting return-air duct to furnace.

5. Install 24- X 24-in. sheet metal shield on platform in front of
louvered control panel as shown in Fig. 8.

→

Step 5—Horizontal Crawlspace Installation

The furnace can be installed horizontally with either the LH or RH
side up. In a crawlspace, furnace can either be hung from floor
joist (see Fig. 9) or installed on suitable blocks or pad. (See Fig.

A96285

COMBUSTIBLE

FLOORING

SHEET METAL

PLENUM

FLOOR

OPENING

A96284

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

Box Installed on Combustible Floor

10.) The furnace can be suspended from each corner by hanger
bolts (4 each 3/8-in. all-thread rod) cut to desired length, 1- X
3/8-in. flat washer, 3/8-in. lockwasher, and 3/8-in. nut. Dimples
are provided for hole locations. (See Fig. 1.)

Since horizontal crawlspace installation is very similar to attic
installation, refer to Step 4. The installation of a sheet metal shield
in front of louvered control panel is covered in Step 4. For a
crawlspace installation, this same sheet metal shield must be
installed above louvered control panel. Extend sheet metal shield
over furnace top far enough to cover gas pipe entry hole.

Step 6—Filter Arrangement

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. 11 and
Table 4 for horizontal applications. Horizontal filter retainers must
be field supplied. See Fig. 12 for downflow applications.

Step 7—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.

The gas supply line should be a separate line directly from the
meter to the furnace, if possible. Refer to Table 5 for recom­mended gas pipe sizing. Risers should be used to connect to the
furnace and to the meter.

7

LINE CONTACT ONLY PERMISSIBLE BETWEEN
LINES FORMED BY INTERSECTIONS OF
THE TOP AND TWO SIDES OF THE FURNACE
JACKET AND BUILDING JOISTS,
STUDS, OR FRAMING.

MANUAL SHUTOFF

GAS VALVE

SEDIMENT

TRAP

GAS
ENTRY

MIN

″

6

24

24

″

″

SHEET
METAL

Fig. 8—Typical Attic Installation

TYPE-B
VENT

30-IN. MIN
WORK AREA

A97516

ANGLE
IRON OR
EQUIVALENT

(B)

(A)

ROD LOCATION
USING DIMPLE
LOCATORS
(SEE DIMENSIONAL
DWG FOR
LOCATIONS)

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

→ Fig. 9—Horizontal Crawlspace Installation on Hanger Rods

3

/8-IN. HEX NUT

& WASHER (4)

REQD PER ROD

(B)

(A)

(A)

(B)

NOTES:

3

⁄8-IN. ROD

(A)

(B)

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.

A96633

8