Carrier 58UXT Series Instructions and recipes

58UXT
Upflow/Horizontal, 2-Speed, 2-Stage
Induced-Combustion Gas Furnace
Installation, Start-Up, and Operating Instructions
Size 060-120, Series 100
NOTE: Read the entire instruction manual before starting the
installation.
Index Page
SAFETY CONSIDERATIONS..................................................1-2
Clearances to Combustibles......................................................1
ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS
PROCEDURE........................................................................2-3
Dimensional Drawing ....................................................................2
INTRODUCTION..........................................................................3
LOCATION....................................................................................3
General......................................................................................3
Location Relative to Cooling Equipment ................................3
Hazardous Locations.................................................................4
AIR FOR COMBUSTION AND VENTILATION...................4-5
Unconfined Space.....................................................................4
Confined Space......................................................................4-5
UPFLOW INSTALLATION .........................................................5
HORIZONTAL ATTIC INSTALLATION...................................5
HOROZONTAL CRAWLSPACE INSTALLATION...............5-6
FILTER ARRANGEMENT...........................................................6
LEVELING LEGS (IF REQUIRED)............................................6
GAS PIPING...............................................................................6-7
ELECTRICAL CONNECTIONS...............................................8-9
115-v Wiring..........................................................................8-9
24-v Wiring...............................................................................9
Accessories................................................................................9
VENTING ......................................................................................9
START-UP, ADJUSTMENT, AND
SAFETY CHECK................................................................9-18
General......................................................................................9
Sequence of Operation........................................................9-13
Adaptive Heating Mode....................................................10-11
Non-Adaptive Heating Mode............................................11-12
Cooling Mode .........................................................................12
Continuous Blower Mode.......................................................12
Heat Pump Mode...............................................................12-13
Defrost.....................................................................................13
Start-Up Procedures...........................................................13-14
Adjustments .......................................................................14-17
Set Gas Input Rate ............................................................14-16
Set Temperature Rise........................................................16-17
Set Thermostat Heat Anticipator ......................................17-18
Check Safety Controls............................................................18
Checklist..................................................................................18
SAFETY CONSIDERATIONS
Installation and servicing of 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. 54-1992/ANSI Z223.1-1992.
In Canada, refer to the current edition of the National Standard of
®ama
CANADIAN GAS ASSOCIATION
APPROVED
R
Table 1—Minimum Clearances To Combustible
Materials (In.)
UNIT SIZE 060 080—120
UPFLOW
Furnace Sides Single-Wall Vent 1 0
Type B-1 Double-Wall Vent 0 0
Furnace Back 00
Plenum Top 11
Furnace Front (See Notes) Single-Wall Vent 6 6
Type B-1 Double-Wall Vent 3 3
Vent Single-Wall Vent 6 6
Type B-1 Double-Wall Vent 1 1
HORIZONTAL POSITION (IN ALCOVE, ATTIC,
AND CRAWLSPACE)
Sides* 11
Back 00
Top Single-Wall Vent 1 1
Type B-1 Double-Wall Vent 1 1
Furnace Front† (See Notes) Single-Wall Vent 6 6
Type B-1 Double-Wall Vent 3 3
Vent Single-Wall Vent 6 6
Type B-1 Double-Wall Vent 1 1
HORIZONTAL POSITION (IN CLOSET)**
Sides*‡ 11
Back 00
Top Single-Wall Vent 2 2
Type B-1 Double-Wall Vent 2 2
Furnace Front
(See Notes) Single-Wall Vent 6 6
Type B-1 Double-Wall Vent 3 3
Vent Single-Wall Vent 6 6
Type B-1 Double-Wall Vent 1 1
* Supply side must maintain 6 in. clearance from flue to combustible materials
when using single-wall vent.
† 18 in. front clearance required for alcove.
‡ Indicates supply or return sides when furnace is in horizontal position. Line
contact only permissible between lines formed by intersections of top and two
sides of furnace jacket, building joists, studs, or framing. Clearance to return
side is 0 in.
** J-Box must be installed on lower (bottom) inside of furnace.
NOTES:
1. Provide 30-In. front clearance for servicing. An open door in front of furnace
can meet this requirement.
2. A minimum clearance of 3 In. must be provided in front of furnace for
combustion air and proper operation.
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. 535-847 Printed in U.S.A. Form 58UXT-1SI Pg 1 7-95 Replaces: New
→

Canada CAN/CGA- B149.1- and .2-M91 Natural Gas and Propane
Installation Codes Amendment No. 1 and (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 furnace and in instructions or
manuals, be alert to the potential for personal injury.
Understand the signal words DANGER, WARNING, and CAU-
TION. These words are used with the safety-alert symbol. DAN-
GER identifies the most serious hazards which will result in severe
personal injury or death. WARNING signifies a hazard 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 residen-
tial construction practices. We require these instructions as a
minimum for a safe installation.
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 pre-
vent 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 CON-
TROL PRIOR TO DISCHARGING YOUR BODY’S ELEC-
TROSTATIC 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
Table 2—Dimensions (In.)
UNIT SIZE A D E FLUE COLLAR SHIP. WT(LB)
060-12 14-3/16 12-9/16 12-11/16 4 134
080-16 21 19-3/8 19-1/2 4 154
100-16 21 19-3/8 19-1/2 4 166
100-20 24-1/2 22-7/8 23 4 184
120-20 24-1/2 22-7/8 23 5 194
Fig. 1—Dimensional Drawing A88367
A
D13⁄16″
E11⁄16″
11⁄16″
28 1⁄2″
39 7⁄8″
24 5⁄16″
11⁄16″3″
2 1⁄16″
1″
12 5⁄16″
5 3⁄8″
5 13⁄16″
2 3⁄8″
AIR INLET
7⁄8-IN. DIA HOLE
POWER ENTRY
7⁄8-IN. DIA
ACCESSORY
1 3⁄4-IN.DIA HOLE
GAS ENTRY
1⁄2-IN. DIA HOLE
THERMOSTAT
WIRE ENTRY
SIDE INLET
FLUE COLLAR
NOTE:
Minimum return-air opening at furnace:
1. For 800 CFM–16-In. round or 141⁄2x 12-In. rectangle.
2. For 1200 CFM–20-In. round or 141⁄2x 191⁄2-In. rectangle.
3. For 1600 CFM–22-In. round or 141⁄2x 231⁄4-In. rectangle.
4. For airflow requirements above 1800 CFM, use both side inlets,
a combination of 1 side inlet and the bottom, or the bottom only.
2 additional 7⁄8In. Dia knockouts are located in the top plate.
NOTES:
5 3⁄8″
5 13⁄16″
2 3⁄8″
2 11⁄16″
1″
2 1⁄16″19″
13⁄16″
7⁄8-IN. DIA
POWER ENTRY
AIRFLOW
OUTLET
1 1⁄2-IN.DIA
R.H. GAS ENTRY
7⁄8-IN. DIA ACCESSORY
1⁄2-IN. DIA THERMOSTAT
WIRE ENTRY
SIDE INLET 141⁄2″
1″
231⁄4″
SIDE RETURN
DUCT LOCATION
13⁄4″
TYP 1″
5⁄8″
TYP
2

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 58UXT Series 100 Furnace is available in sizes 60,000
through 120,000 Btuh input capacities.
The design of the upflow/horizontal gas-fired furnace is A.G.A.
and C.G.A. design-certified for use with natural and propane gases
and for installation on combustible wood flooring, in alcoves,
attics, basements, closets, or utility rooms. The design of this
furnace line is not A.G.A. and C.G.A. design-certified for instal-
lation in mobile homes, recreation vehicles, or outdoors.
Before installing the furnace, refer to the current edition of the
NFGC. Canadian installations must be installed in accordance with
NSCNGPIC and all authorities having jurisdiction. For further
information, the NFGC is available from National Fire Protection
Association Inc. Batterymarch Park, Quincy, MA 02269; Ameri-
can Gas Association, 1515 Wilson Boulevard, Arlington, VA
22209; or from Literature Distribution.
Installation must conform to the regulations of the serving gas
supplier and the local building, heating, and plumbing codes in
effect in the area in which the installation is made, or in the
absence of local codes with the requirements of the NFGC.
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.
This furnace is designed for a minimum continuous return-air
temperature of 60°F db or intermittent operation down to 55°F db
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 the blower compartment door. This label
explains how to use the LED status indicator on the furnace control
which is viewed through the sight glass on the door.
Improper installation, adjustment, alteration, service, mainte-
nance, or use can cause carbon monoxide poisoning, explo-
sion, 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 distribu-
tor 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 can cause electrical shock, fire,
personal injury, or death.
For high-altitude installations, the high-altitude conversion kit
MUST be installed at or above 5500 ft above sea level.
For accessory installation details, refer to the applicable installa-
tion literature.
NOTE: Remove all shipping brackets and materials before oper-
ating the furnace.
Step 1—Location
GENERAL
Do not install furnace in a corrosive or contaminated atmo-
sphere. Make sure all combustion and circulating air require-
ments are met.
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 system. 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 the electrical components are
protected from water.
Locate the furnace as near the center of the air distribution system
and chimney or vent as possible. The furnace should be installed
as level as possible. When a furnace is installed so that the supply
ducts carry air to areas outside the space containing the furnace,
the return air must also be handled by a duct(s) sealed to the
furnace casing and terminating outside the space containing the
furnace.
Provide ample space for servicing and cleaning. Always comply
with the minimum fire protection clearances shown on the unit
clearance label. This furnace shall not be installed directly on
carpeting, tile, or any combustible material other than wood
flooring.
LOCATION RELATIVE TO COOLING EQUIPMENT
The cooling coil must be installed parallel with or on the
downstream side of the furnace to avoid condensation in the heat
exchangers. When installed parallel with a furnace, dampers or
other means used to control the flow of air must prevent chilled air
from entering the furnace. If the dampers are manually operated,
they must be equipped with means to prevent operation of either
unit unless the damper is in the full-heat or full-cool position.
3

HAZARDOUS LOCATIONS
When the furnace is installed in a residential garage, it must be
installed so that the burners and ignition source are located at least
18 in. above the floor. The furnace should be protected from
physical damage by vehicles. When a furnace is installed in public
garages, airplane hangars, or other buildings having hazardous
atmospheres, the unit must be installed in accordance with the
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 the local
building codes.
Canadian installations must be in accordance with Section 7 of the
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, deter-
gents, bleaches, cleaning solvents, salts, air fresheners, and
other household products.
All fuel-burning equipment must be supplied with air for combus-
tion of the fuel. Sufficient air MUST be provided to ensure there
will not be a negative pressure in the equipment room or space. In
addition, a positive seal MUST be made between the furnace
cabinet and the return-air duct to prevent pulling air from the
burner area and draft safeguard opening into the circulating air.
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.
The requirements for combustion and ventilation air depend upon
whether the 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 total input for all the appliances (such as furnaces, clothes
dryers, water heaters, etc.) in the space.
For Example:
58UXT FURNACE HIGH-STAGE
INPUT BTUH MINIMUM SQ FT WITH 7-1/2 FT CEILING
60,000 400
80,000 534
100,000 667
117,000 780
If the unconfined space is of unusually tight construction, air for
combustion and ventilation MUST come from either the outdoors
or spaces freely communicating with the 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 an equal or greater amount of air is supplied to the
room.
CONFINED SPACE
A confined space has volume less than 50 cu ft per 1000 Btuh of
the total input rating for all appliances installed in that space. A
confined space MUST have 2 permanent openings, 1 within 12 in.
of the ceiling, and the other within 12 in. of the floor which freely
communicate with an unconfined space or the outdoors. (See Fig.
2.)
NOTE: In determining the free area of an opening, the blocking
effect of the louvers, grilles, and screens must be considered. If the
free area of a louver or grille design is unknown, it may be
assumed 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 the air comes from
outside of the structure or an unconfined space inside the structure.
1. All air from inside the structure:
a. Each opening MUST have at least 1 sq in. of free area per
1000 Btuh of the total input for all equipment within the
confined space, but not less than 100 sq in. per opening.
(See Fig. 2.) The minimum dimension of air openings shall
be not less than 3 in.
For Example:
COMBUSTION AIR FROM UNCONFINED SPACE
58UXT Furnace
High-Stage
Input Btuh
Free Area per Opening
(Sq In.)
60,000 100
80,000 100
100,000 100
117,000 117
b. If the building is constructed unusually tight, a permanent
opening directly communicating with the outdoors should
be provided. This opening shall have a minimum free area
of 1 sq in. per 4000 Btuh of total input rating for all
equipment in the enclosure. (See Fig. 3.)
c. If the furnace is installed on a raised platform to provide a
return-air plenum, and return air is taken directly from the
hallway or space adjacent to the furnace, all air for
combustion must come from outdoors. (See Fig. 3.)
2. All air from outside the structure:
a. If combustion air is taken from outdoors through vertical
ducts, the openings and ducts MUST have at least 1 sq in.
of free area per 4000 Btuh of the total input for all
equipment within the confined space. (See Fig. 3.)
For Example:
COMBUSTION AIR FROM OUTDOORS THROUGH
VERTICAL DUCTS
58UXT Furnace
High-Stage
Input Btuh
Free Area per Opening
(Sq In.) Round Pipe (In. Dia)
60,000 15.0 5
80,000 20.0 6
100,000 25.0 6
117,000 29.3 7
b. If combustion air is taken from the outdoors through
horizontal ducts, the openings and ducts MUST have at
least 1 sq in. of free area per 2000 Btuh of the total input
for all equipment within the confined space. (See Fig. 3.)
4

For Example:
COMBUSTION AIR FROM OUTDOORS THROUGH
HORIZONTAL DUCTS
58UXT Furnace
High-Stage
Input Btuh
Free Area per Opening
(Sq In.) Round Pipe (In. Dia)
60,000 30.0 7
80,000 40.0 8
100,000 50.0 8
117,000 58.5 9
c. 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. 3.)
Step 3—Upflow Installation
Do not install the furnace on its back or sides. Safety control
operation will be adversely affected. Never connect return-air
ducts to the back of the furnace. A failure to follow this
warning can cause a fire, personal injury, or death.
NOTE: Door clip on control door may be removed for upflow
installation.
1. Position furnace in desired location.
2. Connect gas supply pipe.
3. Connect supply- and return-air ducts.
Step 4—Horizontal Attic Installation
Do not install the furnace on its back or sides. Safety control
operation will be adversely affected. Never connect return-air
ducts to the back of the furnace. A failure to follow this
warning can cause a fire, personal injury, or death.
The furnace can be installed horizontally with either the left-hand
(LH) or right-hand (RH) side down. A typical attic installation is
shown in Fig. 4.
CONSTRUCT A WORKING PLATFORM
Construct working platform on location where all required furnace
clearances are met. (See Table 1 and Fig. 4.)
INSTALL FURNACE
1. Position furnace in desired location.
2. Connect gas supply pipe. See Fig. 4 for typical piping entry.
3. Connect supply- and return-air ducts.
4. Install 24- X 24-in. sheet metal shield on platform in front of
louvered control panel as shown in Fig. 4.
Step 5—Horizontal Crawlspace Installation
The furnace can be installed horizontally with either LH or RH
side up. In a crawlspace, the furnace can either be hung from the
floor joist (See Fig. 5) or installed on suitable blocks or pad (See
Fig. 6.) 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 the horizontal crawlspace installation is very similar to the
attic, refer to Horizontal Attic Installation. The installation of a
Fig. 2—Confined Space: Air for Combustion and
Ventilation from an Unconfined Space
A89012
SUPPLY
AIR
6″MIN
(FRONT) †
RETURN AIR
VENT THROUGH ROOF
1 SQ IN.
PER 1000
BTUH*IN DOOR
OR WALL
12″MAX
1 SQ IN.
PER 1000
BTUH*IN DOOR
OR WALL
12″MAX
INTERIOR
HEATED
SPACE
* Minimum opening size is 100 square in. with
minimum dimensions of 3-In.
† Minimum of 3-In. when type-B1 vent is used.
UNCONFINED
SPACE
CONFINED SPACE
Fig. 3—Confined Space: Air for Combustion and
Ventilation from Outdoors
A89013
1 SQ IN.
PER
4000
BTUH*
DUCTS
TO
OUTDOORS
1 SQ IN.
PER 4000
BTUH*
SUPPLY
AIR
VENT
THROUGH
ROOF
D
B
A
C
E
1 SQ IN.
PER 4000
BTUH*
DUCT
TO
OUTDOORS
RETURN AIR
1 SQ IN.
PER 2000
BTUH*
1 SQ IN.
PER 2000
BTUH*
DUCTS
TO
OUTDOORS
12″MAX
12″MAX 12″MAX
Use any of the following
combinations of openings:
A & B C & D D & E F & G
NOTE:
*Minimum dimensions of 3-In.
CONFINED SPACE
12″
MAX
12″
MAX
OUTDOORS
1 SQ IN.
PER
4000
BTUH*
F
G
5

sheet metal shield in front of the louvered control panel is covered
in Horizontal Attic Installation. For a crawlspace installation, this
same sheet metal shield must be installed above the louvered
control panel. Extend the 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 can cause a fire,
personal injury, or death.
The factory-supplied filter(s) is shipped in the blower compart-
ment. Determine location for the filter and move filter retaining
hardware, if necessary, before attaching the return-air duct. After
the return-air duct has been connected to the furnace, install the
filter(s) inside the furnace blower compartment. See Fig. 7 for side
return application and Fig. 8 for bottom return application.
A bottom closure panel is factory installed in the bottom of the
furnace. When bottom return inlet is desired, remove and discard
the enclosure panel.
Filter retaining brackets, supports, and retainers are factory as-
sembled and shipped installed for side return application, with 1
set of all required hardware on each furnace. (See Fig. 7.)
For bottom return applications, remove the front and back brackets
and supports from each side. The back bracket(s) are installed in
the rear of the furnace casing. Dimples are provided to mark
mounting screw locations.
The front bracket(s) are installed on the bottom front plate, as
shown in Fig. 8, once the bottom enclosure has been removed.
Rotate filter supports 180° so filter will rest on support and
reinstall. Install small U-shaped end of filter retaining rod in the
rear bracket. Install the front of filter retainer rod as shown in Fig.
8. Two sets of hardware are needed for furnaces in 24-1/2 in.
casings using 2 filters for bottom return. All hardware is provided
for filter installation.
Step 7—Leveling Legs (If Required)
When the furnace is used with side inlet(s) and leveling legs are
required, refer to Fig. 9 and install field-supplied, corrosion-
resistant 5/16-in. machine bolts and nuts.
NOTE: The length of the bolt should not exceed 1-1/2 in.
1. Lay furnace on its back. Locate and drill 5/16-in. diameter
hole in each bottom corner of furnace as shown in Fig. 9.
2. Install nut on bolt and install bolt with 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.
Step 8—Gas Piping
Emissions control devices located at heat exchanger inlets
MUST be removed for propane installations. (Refer to gas
conversion kit for instructions.)
Gas piping must be installed in accordance with national and local
codes. Refer to the NFGC in U.S. Canadian installations must be
installed in accordance with NSCNGPIC and all authorities having
jurisdiction.
The gas supply line should be a separate line running directly from
the gas meter to the furnace, if possible. Refer to Table 4 for the
recommended gas pipe size. Risers must be used to connect to the
furnace and the meter.
If a flexible connector is required or allowed by the authority
having jurisdiction, black iron pipe shall be installed at
furnace gas control valve and extend a minimum of 2 in.
outside the furnace casing. A failure to follow this warning
could result in fire, personal injury, or death.
Piping should be pressure tested in accordance with local and
national plumbing and gas codes BEFORE the furnace has been
attached. If the test pressure exceeds 0.5 psig (14-in. wc), the gas
supply pipe must be disconnected from the furnace and capped
before the pressure test. If the test pressure is equal to or less than
0.5 psig (14-in. wc), close the manual shut-off valve before the
Fig. 4—Horizontal Attic Installation A95233
30-IN. MIN
WORK AREA
6″ MIN
FLUE VENT
GAS
ENTRY MANUAL SHUTOFF
GAS VALVE
24 ″
24 ″
SHEET
METAL
SEDIMENT TRAP
LINE CONTACT ONLY PERMISSIBLE BETWEEN
LINES FORMED BY INTERSECTIONS OF
THE TOP AND TWO SIDES OF THE FURNACE
JACKET, BUILDING JOISTS,
STUDS, OR FRAMING.
CLEARANCE
TO COMBUSTABLE
MATERIALS
6

test. (See Fig.10.) It is recommended that the ground joint union be
loosened before pressure testing. After all connections have been
made, purge the lines and check for leakage with regulated gas
supply pressure.
Install a sediment trap in the riser leading to the furnace. The trap
can be installed by connecting a tee to the riser leading from the
furnace. Connect a capped nipple into the lower end of the tee. The
capped nipple should extend below the level of the gas controls.
(See Fig. 10.)
Apply joint compound (pipe dope) sparingly and only to the male
threads of each joint. The compound must be resistant to the action
of propane gas.
Install an accessible manual shut-off valve upstream of the furnace
gas controls and within 72 in. of the furnace. A 1/8-in. NPT
plugged tapping is provided on the gas valve for test gage
connection. Installation of an additional 1/8-in. NPT plugged
tapping, accessible for test gage connection, installed immediately
upstream of the gas supply connection to the furnace and down-
stream of the manual shut-off valve, is not required. Place ground
joint union between the gas control manifold and the manual
shut-off valve.
Use the proper length of pipes to avoid stress on the gas
control manifold. A failure to follow this warning can cause
a gas leak resulting in a fire, explosion, personal injury, or
death.
Fig. 5—Crawlspace Horizontal Installation A95234
NOTES:
ANGLE
IRON OR
EQUIVALENT
ROD LOCATION
USING DIMPLE
LOCATORS
(SEE DIMENSIONAL
DWG FOR
LOCATIONS)
3⁄8-IN. ROD
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.
3/8-IN. HEX NUT
& WASHER (4)
REQD PER ROD
Fig. 6—Horizontal Application Using Blocks A95235
7

Use a backup wrench at the furnace gas control when
connecting the gas pipe to the furnace to avoid damaging gas
controls or manifold.
Never purge a 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. A failure to follow this warning can
cause a fire, explosion, personal injury, or death.
Step 9—Electrical Connections
115-V WIRING
Refer to the unit rating plate or Table 5 for equipment electrical
requirements. The control system requires an earth ground for
proper operation.
Do not connect aluminum wire between disconnect switch
and furnace. Use only copper wire.
Make all electrical connections in accordance with the National
Electrical Code (NEC) ANSI/NFPA 70-1993 and local codes or
Fig. 7—Side Filter Arrangement A95284
FILTER
RETAINER
WASHABLE
FILTER
Fig. 8—Bottom Filter Arrangement A93046
Table 3—Filter Information (In.)
FURNACE
CASING WIDTH FILTER SIZE* FILTER TYPE
Side Return Bottom Return
14-3/16‡ (1) 16 X 25 X 1† (1) 14 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 the frame as marked and folding to the
desired size. Alternate sizes can be ordered from your distributor or dealer.
† Factory-provided with the furnace.
‡ External side filter rack must be used for upflow, right-side return.
Fig. 9—Leveling Leg Installation A89014
1 3⁄4″
1 3⁄4″
1 3⁄4″
1 3⁄4″
5⁄16″
5⁄16″
5⁄16″
5⁄16″
Table 4—Maximum Capacity of Pipe*
NOMINAL
IRON PIPE
SIZE (IN.)
INTERNAL
DIAMETER
(IN.)
LENGTH OF PIPE (FT)
10 20 30 40 50
1/2 0.622 175 120 97 82 73
3/4 0.824 360 250 200 170 151
11.049 680 465 375 320 285
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, NFGC.
Fig. 10—Typical Gas Pipe ArrangementA89417
8

ordinances that might apply. For Canadian installations, all elec-
trical connections must be made in accordance with CSA C22.1
Canadian Electrical Code, or authorities having jurisdiction.
The cabinet MUST have an uninterrupted or unbroken ground
according to NEC ANSI/NFPA 70-1993 and Canadian Elec-
trical 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.
The junction box can be moved to the left-hand side of the furnace
when a left-hand side power supply is desired. Remove the 2
screws holding the junction box. Mount the junction box on the
left-hand side of the furnace. Holes have been provided in casing.
When moved, tuck the wiring harness behind the clip provided to
keep extra wire lengths out of the way.
NOTE: Proper polarity must be maintained for 115-v wiring. If
polarity is incorrect, the furnace control status LED will flash
rapidly and prevent heating operation.
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.
13.) Connect terminal Y/Y2 as shown in Fig. 11 or 12 for proper
cooling operation. Use only AWG No. 18 or larger, color-coded
copper thermostat wire.
The 24-v circuit contains an automotive-type, 3-amp fuse located
on the 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 the fuse needs replacement.
ACCESSORIES
1. Electronic air cleaner (EAC)
A terminal block (EAC-1 [hot] and EAC-2 [neutral]) is
provided for EAC connection. (See Fig. 13.) The terminals are
energized with 115v, 1-amp maximum during blower motor
operation.
2. Humidifier (HUM)
Screw terminals (HUM and Com) are provided for 24-v
humidifier connection. The terminals are energized with 24v,
0.5-amp maximum when the gas valve is energized.
Step 10— Venting
Refer to the enclosed Installation Instructions, GAMA Venting
Table for Category I Furnaces, and Venting Tables for 2- stage
Category I fan-assisted furnaces. In Canada use venting tables
found in CAN/CGA B149.1 or .2-M91 Amendment no. 1. The
horizontal portion of the venting system shall maintain a minimum
of 1/4-in. upward slope per linear ft (away from furnace), and it
shall be rigidly supported every 5 ft or less with hangers or straps
to ensure that there will be no movement after installation.
Step 11—Start-Up, Adjustment, and Safety Check
GENERAL
The furnace must have a 115-v power supply properly connected
and grounded. Correct polarity must be maintained to enable gas
heating operation.
The gas service pressure must not exceed 0.5 psig (14-in. wc), and
no less than 0.16 psig (4.5-in. wc).
This furnace can be installed with either a single-stage heating or
2-stage heating thermostat.
Thermostat wire connections at R and W/W1 are the minimum
required for gas heating operation. W2 must be connected for
2-stage heating thermostats. Y/Y2 and G are required to be
connected to furnace for cooling and heat pumps. G is required for
continuous fan. Com 24-v is required for some clock thermostats.
These connections must be made on the 24-v thermostat terminals
on the control. (See Fig. 13.) Y1 on 2-stage thermostat is required
for 2-stage cooling and 2-stage heat pump.
For single-stage thermostats, connect thermostat R to W/W1 at the
furnace control 24-v thermostat terminals. (See Fig. 11.) For
single-stage thermostats, the control will determine, based on
length of previous heating on and off cycles, when to operate in
low- and high-gas heat for optimum comfort. Setup switch-2
(SW-2) must be in the factory-shipped OFF position. See Fig. 14
and Tables 7 and 8 for setup switch information.
If a 2-stage heating thermostat is to be used, move SW-2 to the ON
position at the end of the furnace installation. This overrides the
built-in control process for selecting high and low fire and allows
the 2-stage thermostat to select gas heating modes. The W2 from
the thermostat must be connected to W2 on the control terminal
block. (See Fig. 12.)
This furnace is equipped with a manual reset limit switch in
the gas control area. The switch will open and shut off power
to the gas valve if a flame rollout or overheating condition
occurs in the gas control area. DO NOT bypass the switch.
Correct inadequate combustion-air supply, component fail-
ure, or restricted flue gas passageway before resetting the
switch.
Before operating the furnace, check each manual reset switch for
continuity. If necessary, press and release the button to reset the
switch.
SEQUENCE OF OPERATION
Using the schematic diagram in Fig. 15, follow the sequence of
operation through the different modes. Read and follow the
diagram very carefully.
Table 5—Electrical Data
UNIT SIZE VOLTS— HERTZ—
PHASE
OPERATING
VOLTAGE RANGE MAX
UNIT
AMPS
MIN
WIRE
GAGE
MAX WIRE
LENGTH (FT)‡
MAX FUSE OR
HACR-TYPE
CKT BKR AMPS†
Max* Min*
060-12 115—60—1 127 104 11.4 14 32 15
080-16 115—60—1 127 104 13.5 14 27 15
100-16 115—60—1 127 104 13.2 14 28 15
100-20 115—60—1 127 104 19.0 12 30 20
120-20 115—60—1 127 104 18.2 12 31 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.
9

NOTE: If a power interruption occurs during a "call for heat"
(W/W1 or W/W1 and W2) and if the thermostat is still calling for
gas heating, the control will start a 90-sec blower only on period
2 sec after power is restored. The red LED will flash code 12
during the 90-sec period, after which the LED will be on
continuously as long as no faults are detected. After the 90-sec
period, the furnace will respond to the thermostat normally.
The blower door must be installed for power to be conducted
through the blower door interlock switch ILK to the furnace
control CPU, transformer TRAN, inducer motor IDM, blower
motor BLWM, hot surface ignitor HSI, and gas valve GV.
1. Adaptive Heating Mode—Single-Stage Thermostat with
2-Stage Heating
(See Fig. 11 for thermostat connections.)
NOTE: In response to thermostat call for heat R to W/W1, the
control selects high-stage gas heating only with HIGH HEAT
ONLY switch (SW1) set to ON regardless of the LOW HEAT
switch (SW2) setting. With the HIGH HEAT ONLY switch set to
OFF, LOW HEAT switch selects either low-stage gas heating only
mode when set to ON, or the adaptive heating mode when set to
OFF in response to a thermostat call for heat R to W/W1. (See Fig.
14 for description of switch settings or Fig. 16 for control circuit
diagram.)
This furnace can operate as a 2-stage furnace with a single-
stage thermostat because the furnace control CPU includes a
programmed adaptive sequence of controlled operation, which
Fig. 11—Heating and Cooling Application Wiring Diagram 1-Stage Thermostat and Condensing Unit
A95236
115-VOLT FIELD-
SUPPLIED
FUSED
DISCONNECT
JUNCTION
BOX CONTROL
BOX
24-VOLT
TERMINAL
BLOCK
THREE-WIRE
HEATING-
ONLY
FIVE
WIRE
NOTE 2
NOTE 1
1-STAGE
THERMOSTAT
TERMINALS
FIELD-SUPPLIED
FUSED DISCONNECT
CONDENSING
UNIT
FURNACE
COM
R

WCY RG
GND
GND
FIELD 24-VOLT WIRING
FIELD 115-, 208/230-, 460-VOLT WIRING
FACTORY 24-VOLT WIRING
FACTORY 115-VOLT WIRING
Connect Y/Y2-terminal as shown for proper operation.
Some thermostats require a "C" terminal connection as shown.
If any of the original wire, as supplied, must be replaced, use
same type or equivalent wire.
208/230- OR
460-VOLT
THREE
PHASE
208/230-
VOLT
SINGLE
PHASE
WHT
BLK
WHT
BLK
W/W1
W2
Y/Y2
G
NOTES: 1.
2.
3.
Fig. 12—Heating and Cooling Application Wiring Diagram 2-Stage Thermostat and Condensing Unit
A95332
115-VOLT FIELD-
SUPPLIED
FUSED
DISCONNECT
JUNCTION
BOX CONTROL
BOX
24-VOLT
TERMINAL
BLOCK
FOUR-WIRE
HEATING-
ONLY
SEVEN
WIRE
2-STAGE
THERMOSTAT
TERMINALS FIELD-SUPPLIED
FUSED DISCONNECT
2-SPEED
CONDENSING
UNIT
FURNACE
G
R

W2 Y2 G Y1
GND
GND
FIELD 24-VOLT WIRING
FIELD 115-, 208/230-, 460-VOLT WIRING
FACTORY 24-VOLT WIRING
FACTORY 115-VOLT WIRING
208/230- OR
460-VOLT
THREE
PHASE
208/230-
VOLT
SINGLE
PHASE
 
Y2
Y1
C
WHT
BLK
WHT
BLK
W1CR
W2
COM
W/W1
Y/Y2
NOTE 2
NOTE 1
Connect Y/Y2-terminal as shown for proper operation.
Some thermostats require a "C" terminal connection as shown.
If any of the original wire, as supplied, must be replaced, use
same type or equivalent wire.
NOTES: 1.
2.
3.
10