Induced Combustion Gas Furnace

Owner's Manual
NOTE TO INSTALLER:
THIS MANUAL MUST BE LEFT WITH THE S I GN
DE
EQUIPMENT USER.
ER

D
C
TIFIE ISO 9001
USER: PLEASE READ ALL INSTRUCTIONS QMI-SAI Global

IN THE MANUAL AND RETAIN ALL

MANUALS FOR FUTURE REFERENCE.
Use of the AHRI Certified TM Mark indicates a
manufacturer’s participation in the program. For
Our products are designed, tested and built in accordance with verification of certification for individual products,
Department of Energy (DOE) standardized procedures; however, go to www.ahridirectory.org.
actual operating results and efficiencies may vary based on
manufacturing and supplier tolerances, equipment configuration,
operating conditions and installation practices.

! WARNING
FIRE OR EXPLOSION HAZARD
Failure to follow safety warnings exactly could result in
serious injury, death, or property damage.
Do not store or use gasoline or other flammable vapors and
liquids in the vicinity of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS
−Do not try to light any appliance.
−Do not touch any electrical switch; do not use any
phone in your building.
−Leave the building immediately.
−Immediately call your gas supplier from a neighbor’s
phone. Follow the gas supplier’s instructions.
−If you cannot reach your gas supplier, call the fire
department.
Installation and service must be performed by a qualified
installer, service agency or the gas supplier.

! WARNING
CARBON MONOXIDE POISONING HAZARD
Failure to follow this warning could result in personal
A10247 injury and/or death.
Carbon Monoxide is invisible, odorless, and toxic! Carrier
Corp. recommends a carbon monoxide alarm in your home,
even if you do not own a gas appliance. Locate the carbon
monoxide alarm in the living area of your home and away
from gas appliances and doorways to attached garages.
Follow the alarm manufacturer’s instruction included with
the alarm.

1
 FURNACE COMPONENTS
! WARNING (Furnace shown in upflow position; may be used in downflow or
horizontal orientation or applications. Vent Elbow may be turned
ELECTRICAL OPERATION HAZARD to a different position, depending on type of installation)
Failure to follow this warning could result in personal injury, INDUCER MOTOR VENT
death, or property damage. ASSEMBLY ELBOW

Do not use this furnace if any part has been under water. A PRESSURE
MAIN LIMIT SWITCH
(BEHIND GAS VALVE)

flood−damaged furnace is extremely dangerous. Attempts to SWITCH

use the furnace can result in fire or explosion. A qualified BLOCKED VENT
SWITCH
service agency should be contacted to inspect the furnace and FLUE COLLECTOR
BOX
to replace all gas controls, control system parts, electrical parts FLAME
SENSOR
that have been wet or the furnace if deemed necessary. GAS VALVE

WELCOME TO TODAY’S GENERATION MANUAL RESET

LIMIT SWITCHES
GAS MANIFOLD

OF COMFORT HOT SURFACE

IGNITOR
Congratulations! Your new, higher efficiency gas furnace is a GAS BURNER

sound investment which will reward you and your family with BLOWER

years of warm memories winter after winter.

DOOR SAFETY
SWITCH

Not only is your new furnace energy efficient, it is also extremely FURNACE
CONTROL
BLOWER AND
reliable. Spend just a few minutes with this booklet to learn about
BOARD
MOTOR

the operation of your new furnace—and the small amount of

maintenance it takes to keep it operating at peak efficiency. Years
CAPACITOR/
POWER CHOKE

went into the development of your new furnace. Take a little time
now to assure its most efficient operation for years to come.

TABLE OF CONTENTS A10259

WELCOME TO TODAY’S GENERATION OF COMFORT . . 2 Fig. 1 − 80% AFUE Single Stage Furnace Components
FURNACE COMPONENTS . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
GENERAL FURNACE SAFETY . . . . . . . . . . . . . . . . . . . . . . . 2 INDUCER MOTOR VENT
ASSEMBLY ELBOW
IMPORTANT FACTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . . . . . . 3 PRESSURE
MAIN LIMIT SWITCH
(BEHIND GAS VALVE)
SWITCHES
BEFORE STARTING YOUR FURNACE . . . . . . . . . . . . . . . . . 3
BLOCKED VENT
STARTING YOUR FURNACE . . . . . . . . . . . . . . . . . . . . . . . . . 3 FLUE COLLECTOR
SWITCH

Steps for Starting Your Furnace . . . . . . . . . . . . . . . . . . . . . . . . 4

BOX
FLAME
SENSOR
GAS VALVE
SHUTTING DOWN YOUR FURNACE . . . . . . . . . . . . . . . . . . 5
PERFORMING ROUTINE MAINTENANCE . . . . . . . . . . . . . 5
Filtering Out Trouble . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 MANUAL RESET
LIMIT SWITCHES
GAS MANIFOLD

COMBUSTION AREA AND VENT SYSTEM . . . . . . . . . . . . 8

BEFORE YOU REQUEST A SERVICE CALL . . . . . . . . . . . . 9 HOT SURFACE
IGNITOR

REGULAR DEALER MAINTENANCE . . . . . . . . . . . . . . . . 10 GAS BURNER

INSTALLATION DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 BLOWER DOOR

SAFETY SWITCH

GENERAL FURNACE SAFETY

FURNACE CONTROL
BOARD
BLOWER AND
MOTOR

FIRE OR EXPLOSION HAZARD WARNING . . . . . . . . . . . . . 1

CARBON MONOXIDE WARNING . . . . . . . . . . . . . . . . . . . . 1
CAPACITOR/
POWER CHOKE

FLOOD DAMAGE WARNING . . . . . . . . . . . . . . . . . . . . . . . . 2

COMBUSTIBLE MATERIALS, GASOLINE WARNING . . . . 3
FURNACE MUST BE KEPT FREE AND CLEAR OF
INSULATING MATERIAL WARNING . . . . . . . . . . . . . . . . . . 3
PROPER FURNACE SHUTDOWN PROCEDURES . . . . . . . . 5
A10260
SERVICE AND MAINTENANCE ELECTRICAL HAZARD Fig. 2 − 80% AFUE Two−Stage Furnace Components
WARNING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
SHARP EDGES CAUTION . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
IMPORTANT FACTS (DO’S AND DON’TS)
NO FILTER CAUTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
S DO: READ AND UNDERSTAND THIS MANUAL.
FILTER ROD MODIFICATION CAUTION . . . . . . . . . . . . . . 7
S DO: Have your furnace and vent system inspected annually by a
IMPROPER VENT WARNING . . . . . . . . . . . . . . . . . . . . . . . . . 8
qualified service technician.
DIRT, RUST, OR ACCUMULATION CAUTION . . . . . . . . . . 8
S DO: Inspect your filter monthly and clean or replace when
FURNACE NEEDS AIR FOR COMBUSTION AND
VENTILATION WARNING . . . . . . . . . . . . . . . . . . . . . . . . . . 8 needed.
DRAFT SAFEGUARD SWITCH CAUTION . . . . . . . . . . . . . 9 S DO: Provide adequate airflow to the furnace for efficient
combustion and safe ventilation.

2
S DO: Keep your furnace free and clear of insulating material. SAFETY CONSIDERATIONS
Some materials may be combustible. Examine the furnace area Installing and servicing heating equipment can be hazardous due to
when the furnace is installed or when insulation is added. gas and electrical components. Only trained and qualified
S DO NOT: Enclose your furnace in an airtight room or seal it personnel should install, repair, or service heating equipment.
behind solid doors. Untrained personnel can perform basic maintenance functions such
as cleaning or replacing air filters. All other operations must be
S DO NOT: Keep combustible materials, gasoline, and other
performed by trained service personnel. Observe safety precautions
flammable liquids or vapors around your furnace. in this manual, on tags, and on labels attached to the furnace, and
S DO NOT: Cover your furnace in any manner. other safety precautions that may apply.
S DO NOT: Store anything (including trash or debris) near your Recognize safety information. This is the safety−alert symbol .
furnace. When you see this symbol on the furnace and in instructions or
S DO NOT: In any way block or restrict airflow around your manuals, be alert to the potential for personal injury.
furnace. Understand the signal words DANGER, WARNING, and
S DO NOT: In any way block or restrict airflow to your supply air CAUTION. These words are used with the safety−alert symbol.
DANGER identifies the most serious hazards which will result in
and return air grills. severe personal injury or death. WARNING signifies hazards
S DO NOT: Use your furnace room as a broom closet or a place to which could result in personal injury or death. CAUTION is used
store any kind of chemical or cleaner. to identify unsafe practices which would result in minor personal
S DO NOT: Contaminate the air used for combustion of your injury or product and property damage. NOTE is used to highlight
suggestions which will result in enhanced installation, reliability or
furnace with any kind of chemical or fumes. This could also operation.
cause heat exchangers, metal vent systems or components to
BEFORE STARTING YOUR FURNACE
deteriorate.
Examine the furnace installation to determine that:
NOTE: These chemicals or fumes are present in many products
1. All flue gas carrying areas external to the furnace (i.e.
around the home, such as: water softener salts, any type of
chimney, vent connector) are clear and free of obstructions.
household cleaning product, any type of laundry product,
2. The vent connector is in place, slopes upward and is
adhesives, paints, varnishes, paint strippers, waxes and plastics, etc.
physically sound without holes or excessive corrosion.
During remodeling be sure the combustion air is fresh and 3. The return−air duct connection(s) is physically sound, is
uncontaminated. If these compounds are burned in your furnace, sealed to the furnace casing, and terminates outside the
the heat exchangers and metal vent system may deteriorate. space containing the furnace.
NOTE: The qualified installer or agency must use only 4. The physical support of the furnace is sound without
factory−authorized replacement parts, kits, and accessories when sagging cracks, gaps, etc. around the base.
modifying this product. 5. There are no obvious signs of deterioration of the furnace.
This furnace contains safety devices which must be manually reset.
If the furnace is left unattended for an extended period of time,
STARTING YOUR FURNACE
have it checked periodically for proper operation. This precaution Your furnace uses an automatic, hot surface ignition system to light
will prevent problems associated with no heat, such as frozen water the burners each time the thermostat signals the furnace to start.
pipes, etc. See “Before You Request a Service Call” section in this
manual. Follow these important safeguards:
S Never attempt to manually light the burners with a match
! WARNING or other source of flame.

FIRE OR EXPLOSION HAZARD

Failure to follow this warning could result in injury, death, or
property damage.
Do not keep combustible materials, gasoline, and other
flammable liquids or vapors around your furnace.

! WARNING Fig. 3 − Do Not Light Burner with Match

A92319

FIRE OR EXPLOSION HAZARD S Read and follow the operating instructions on inside of
main furnace door, especially the item that reads as
Failure to follow warnings could result in personal injury,
follows:
death, or property damage.
“Wait 5 minutes to clear out any gas. Then smell for gas,
Keep insulation clear of furnace and maintain clearances including near the floor. If you smell gas, STOP!
shown on unit clearance label. Follow “B” in the safety information above on this
furnace label. If you don’t smell gas, go to the next step.”
S If a suspected malfunction occurs with your gas control
system, such as the burners do not light when they
should, refer to the shutdown procedures on inside of

3
 main furnace door, or in the “Shutting Down Your
Furnace” section and call your dealer as soon as possible.
S Should the gas supply fail to shut off or if overheating
occurs, shut off the gas valve to the furnace before shut-
ting off electrical supply.

! WARNING
FIRE AND EXPLOSION HAZARD
Failure to follow this warning could result in personal
A92185
injury, death or property damage.
Fig. 6 − Turn Off Electrical Supply
Should the gas supply fail to shut off or if overheating
occurs, shut off the gas valve to the furnace BEFORE 4. Remove the outer door by loosening the thumbscrew and
shutting off the electrical supply and install lockout tag. pulling the door forward. See Fig. 7.
1

S CHECK AIR FILTER: Before attempting to start your

furnace, be sure the furnace filter is clean and in place.
2

See “Performing Routine Maintenance” section in this

manual. Do not run the furnace without a filter in place.
Then proceed as follows:
STEPS FOR STARTING YOUR FURNACE
1. Set your room thermostat to the lowest temperature setting.
See Fig. 4.

A10263
Fig. 7 − Remove Furnace Door
5. Turn the control switch on the gas control to the OFF position
and wait 5 minutes. See Fig. 8. Then smell for gas, including
near the floor. If you smell gas, STOP! Follow “B” on furnace
label. If you don’t smell gas, go to next step.

OFF

ON
A09564
OR
Fig. 4 − Lowest Temperature Setting
2. Close the external manual gas valve. See Fig. 5.

CL
O
SE

A02266
Fig. 8 − Control Switch to OFF
6. After waiting 5 minutes, if you still smell gas, STOP! Follow
the safety information on the cover of this manual. If you do
not smell gas, go to the next step.
7. Turn the control switch to ON. See Fig. 9.

A06188
Fig. 5 − Close Valve
3. Turn OFF electrical supply to the furnace. See Fig. 6.

4
 the furnace’s heat exchanger. After a time delay of approxim-
ately 25−45 seconds the furnace blower is switched on.
NOTE: If the main burners fail to ignite, the furnace control

OFF

ON
system will go through three more ignition cycles. Then if burners
OR fail to ignite, the system will lockout. If lockout occurs or the
blower does not come on, shut down your furnace and call your
dealer for service.
13. Set your thermostat to the temperature that satisfies your
comfort requirements. SUGGESTION: Setting the
thermostat back a few degrees—and compensating for the
A02267
difference with warmer clothing—can make a big difference
Fig. 9 − Control Switch to ON
in your fuel consumption on extremely cold days. The few
8. Replace the outer door and tighten the thumbscrew. See Fig. degrees at the top of your thermostat “comfort level” are the
10. most costly degrees to obtain.
3
When the room temperature drops below the temperature selected
on the thermostat, the furnace will switch on automatically. When
2
the room temperature reaches the setting selected on the thermostat,
the furnace will be automatically switched off.
Continuous Fan Operation −Some thermostats have a “FAN”
switch with 2 selections: AUTO and ON. When thermostat is set
on AUTO, the furnace blower cycles on and off, controlled by the
thermostat. In ON position, the furnace blower runs continuously
except for a 42−62 sec delay at the “call for heat.” Continuous fan
keeps the temperature level in your home more evenly balanced. It
also continuously filters the indoor air.
Comfort Fant −On all but the 58STA or 58STX, the continuous
fan blower speed can be increased or decreased if desired due to
1

change of seasons, large gatherings in your home, etc. Simply

A10264 change your “FAN” switch from “on” to “off” (or “auto”
Fig. 10 − Furnace Door Replaced depending on your thermostat), and then return to “on”, within 1 to
3 seconds. The blower will switch to the next highest speed. There
9. Turn ON the electrical supply to the furnace. See Fig. 11.
are at least 3 speeds to choose from. If the blower is running on its
highest speed, a request to change will direct the blower to return
to its lowest speed.
SHUTTING DOWN YOUR FURNACE
Should you ever suspect a malfunction in your furnace, you will
need to turn the furnace off. The following procedures must be
followed:
1. Set your room thermostat to the lowest temperature setting.
(See Fig. 3.)
2. Close the external manual gas valve (See Fig. 4).
3. Turn off electrical supply to the furnace. (See Fig. 6.)
A92359 4. Remove outer furnace door. (See Fig. 7.)
Fig. 11 − Turn On Electrical Supply 5. Turn the switch on the gas control to the OFF position. (See
Fig. 8.)
10. Open the external manual gas valve. See Fig. 12.
6. Replace the outer furnace door. (See Fig. 10.)
7. If the furnace is being shut down because of a malfunction, call
OP your dealer as soon as possible.
PERFORMING ROUTINE MAINTENANCE
EN

With proper maintenance and care, your furnace will operate

economically and dependably. Instructions for basic maintenance
are found on this and the following pages. However, before
beginning maintenance, follow these safety precautions:

A06189
! WARNING
Fig. 12 − Open Valve ELECTRICAL SHOCK HAZARD
11. Set the room thermostat to a temperature slightly above the Failure to follow this warning could result in personal
room temperature. This will automatically signal the furnace injury or death.
to start. The inducer motor will start and the hot surface igniter Turn off electrical power supply to your furnace before
will energize. When hot, the igniter will have an orange glow. removing the access doors to service or perform
12. After about 17 seconds, the gas valve permits gas to flow to the maintenance.
main burners where it is ignited. Hot flames begin to warm

5
 ! CAUTION
CUT HAZARD
Failure to follow this caution may result in personal injury.
Although special care has been taken to minimize sharp
edges, be extremely careful when handling parts or reaching
into the furnace. Wear safety glasses, gloves, and
appropriate protective clothing.

FILTERING OUT TROUBLE

! CAUTION Representative drawing only, some model may vary.

A06190
UNIT PERFORMANCE HAZARD Fig. 14 − Removing Side Filter Cabinet Door
Failure to follow this caution may result in product damage.
Never operate your furnace without a filter in place. Doing
so may damage the furnace blower motor. An
accumulation of dust and lint on internal parts of your
furnace can cause a loss of efficiency.

A dirty filter will cause excessive stress on the furnace, heat

exchanger, and blower motor and can cause it to overheat and
automatically shut down. The furnace filter should be checked
every 4 weeks and cleaned or replaced if necessary.
If installed with factory specified disposable media filter, check or
replace filter before each heating and cooling season. Replace
disposable media filter at least twice a year.
If your furnace filter needs replacing, be sure to use the same size Representative drawing only, some model may vary.
and type of filter that was originally specified. A06191
The air filter for the furnace may be located in a filter cabinet/rack Fig. 15 − Removing Bottom Filter Cabinet Door
attached to the side or bottom of the furnace. If air filter has been
installed in another location, contact your dealer for instructions. 4. Slide air filter out of filter cabinet. Keep dirty side up (if
To inspect, clean and/or replace the air filter(s), follow these steps: dirty) to avoid spilling dirt. (See Fig. 16 and 17.)
1. Turn off the electrical supply to the furnace. See Fig. 13.

A92185
Fig. 13 − Turn Off Electrical Supply
Representative drawing only, some model may vary.
2. Remove filter cabinet door/rack.
A00227
3. Remove filter cabinet door (See Fig. 14 and 15.) Fig. 16 − Slide Side Filter Out of Furnace
NOTE: It may be necessary to remove 1 thumbscrew.

6
 Representative drawing only, some model may vary. Representative drawing only, some model may vary.
A00228 A06193
Fig. 17 − Slide Bottom Filter Out of Furnace Fig. 19 − Replace Bottom Filter Cabinet Door
5. Inspect the filter. If torn, replace it. NOTE: If side return ducts are used, 2 filters may be required in
NOTE: If a washable filter has been replaced with: some models. The procedure listed above may be used to remove
a. Factory specified disposable media filter — Do not side filters.
clean. If dirty, replace only with media filter having the
same part number and size. Install with airflow direction
arrow pointing towards blower (some models may
! CAUTION
vary). PERSONAL INJURY HAZARD
b. Electronic Air Cleaner (EAC) — Refer to EAC
Failure to follow this caution may result in personal injury.
Owner’s Manual for maintenance information (some
models may vary). Use care when cutting support rods in filters to protect against
flying pieces and sharp rod ends. Wear safety glasses, gloves,
6. Wash filter (if dirty) in sink, bathtub, or outside with a
and appropriate protective clothing.
garden hose. Always use cold tap water. A mild liquid de-
tergent may be used if necessary. Spray water through filter
in the opposite direction of airflow. Allow filter to dry.
Filters may be field modified by cutting filter material and support
7. Reinstall clean air filter.
rods three (3) in filters. Alternate sizes and additional filters may be
8. Replace filter cabinet door. (See Fig. 18 and 19.) ordered from your dealer.
9. Turn on electrical supply to furnace (See Fig. 11).
10. Reinstall clean air filter.
11. Replace filter cabinet door.
12. Turn on electrical supply to furnace (See Fig. 11).
NOTE: If side return ducts are used, two (2) filters may be
required in some models. The procedure listed above may be used
to remove side filters.

Representative drawing only, some model may vary.

A06192
Fig. 18 − Replace Side Filter Cabinet Door

7
 FILTER QUANTITY AND SIZE *
FURNACE CASING WIDTH **
FILTER TYPE*
IN (MM) SIDE RETURN BOTTOM RETURN
IN (MM) IN (MM)
(1) 16 x 25 (1) 14 x 25 3/4” (19 mm) thick washable or 4-5/16” (110 mm)
14-1/2 (368)
(406 x 635) (356 x 635) thick media-type
(1) 16 x 25 (1) 16 x 25 3/4” (19 mm) thick washable or 4-5/16” (110 mm)
17-1/2 (445)
(406 x 635) (406 x 635) thick media-type
(1) 16 x 25 (1) 20 x 25 3/4” (19 mm) thick washable
21 (533 )
(406 x 635) (508 x 635) or 4-5/16” (100 mm) thick media-type
(1) 16 x 25 (1) 24 x 25 3/4” (19 mm) thick washable or 4-5/16” (100 mm)
24 (610)
(406 x 635) (610 x 635) thick media-type
*Recommended
**Some furnaces may have 2 filters

COMBUSTION AREA AND VENT SYSTEM

! WARNING
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury
or death.
For proper and safe operation the furnace needs air for
combustion and ventilation. Do not block or obstruct air
openings on the furnace, air opening to the area in which the
furnace is installed, and the space around the furnace.
A92330
Fig. 20 − Burner Flame

! CAUTION ! WARNING
UNIT OPERATION HAZARD
CARBON MONOXIDE POISONING HAZARD
Failure to follow this caution may result in personal injury.
Failure to follow this warning could result in personal
Failure to follow this warning could result in personal injury injury or death.
or death.
If dirt, rust, soot, or scale accumulations are found, call
For proper and safe operation the furnace needs air for your dealer. Do not operate your furnace.
combustion and ventilation. Do not block or obstruct air
openings on the furnace, air opening to the area in which the 3. Inspect the vent pipe for a sag, holes, or a disconnection. A
furnace is installed, and the space around the furnace. horizontal vent pipe must slope upward away from furnace.
If rusty joints or seams, or signs of water leakages are
found, call your dealer for service.
Inspect the combustion area and vent system before each heating

WARNING
season. An accumulation of dirt, soot, or rust can mean a loss of
efficiency and improper performance. Buildups on the main !
burners can cause faulty firing. This “delayed ignition” is
characterized by an alarmingly loud sound. CARBON MONOXIDE POISONING HAZARD
NOTE: If your furnace makes a loud noise when the main burners Failure to follow this warning could result in personal injury
are ignited, shut down the furnace and call your servicing dealer. or death.
Use your flashlight and follow these steps for inspecting the If holes are found or if the vent pipe is obstructed or is not
combustion area and vent system of your furnace: connected, toxic fumes can escape into your home. DO NOT
1. Turn off electrical supply to the furnace and remove the OPERATE YOUR FURNACE. Call your dealer for service.
access door. (See Fig. 6 and 7.)
2. Carefully inspect the gas burner for dirt, rust, or scale.
Inspect the elbow, flue connection area, and the vent pipe 4. Restore electrical power to the furnace. (See Fig. 11.)
for rust. 5. Start the furnace and observe its operation. If possible,
watch the burner flames. Are they burning bright blue? If
not or if you suspect some other malfunction, call your
servicing dealer.
6. Replace the access door. (See Fig. 10.)

8
 BEFORE YOU REQUEST A
“SERVICE CALL”
Before you call for service, check for several easily solved
problems:
S Check for sufficient airflow. Check the air filter for dirt. Check
for blocked return−air or supply−air grilles. Be sure they are
open and unobstructed. If this isn’t the cause of the problem, call
your servicing dealer. If your furnace isn’t operating at all, check
the following list for easily solved problems:
S Is your thermostat set above room temperature? Is the HEAT
mode selected?
S Is the electrical power supply switch on? Is the blower access
door firmly in place? Are any fuses blown? (There is a fuse on
the furnace control.) Has a circuit breaker tripped?
S Is the manual shut−off valve in the gas supply pipe leading to
the furnace open? Does the lever point in the same direction that
the pipe runs (open)? Or is it at a right angle to the pipe (closed)?
NOTE: Before proceeding with the next checks, turn off the
electrical power supply to the furnace. Remove access door.
S Is the switch on the gas valve turned to the ON position? If this
or the preceding check shows an interruption in the gas supply,
make sure the gas has not been shut off for safety reasons. If
nothing else seems to be wrong, follow the start−up procedures
found on pages 4 and 5 of this booklet.

! CAUTION
UNIT OPERATION HAZARD
Failure to follow this caution may result in personal injury.
If for some reason the vent is blocked, the draft safeguard
switch will shut off the furnace. (See Page 2 for switch
location.) The switch will automatically reset after the furnace
cools off. If the furnace fails to operate, contact a qualified
service agency.

S Check the manual reset limit switches located on the ends of the
burner enclosure (see Fig. 1 and 3). If the furnace has
experienced a high−temperature condition due to inadequate
combustion air, these switches will shut off the furnace. Reset
the switches by pushing the button on the switch. If the switch
trips a second time, turn off the furnace and call for service.
S If your furnace still fails to operate, call your servicing dealer for
troubleshooting and repairs. Tell your dealer the model and
serial numbers for your furnace. (You should have them
recorded on page 10 of this booklet.) By knowing exactly which
furnace you have, the dealer may be able to offer suggestions
over the phone or save valuable time through knowledgeable
preparation for the service call.

9
In addition to the type of routine maintenance you might be willing to perform, your furnace should be inspected regularly by a properly
trained service technician. You should work with your dealer or service technician to assure your inspection includes the following at a
minimum.
MAINTENANCE CHECKLIST
INSPECTION INTERVAL
DESCRIPTION
Monthly Bi­annually Annually
Furnace specific, external items:
Clean or replace air filters. X
Inspect cabinet for signs of damage. X
Inspect and clean door louvers if needed. X
Inspect electrical disconnect for proper function. Repair or replace as necessary. X
Inspect external wiring for damage. X
Inspect gas supply line and manual shut­off for leaks. X
Furnace specific, internal items:
Inspect and clean blower assembly (includes blower housing, blower wheel and
X
motor).
Inspect gas valve and check for proper manifold gas pressure Adjust as needed. X
Inspect ignition system and safety controls. Clean and adjust as needed. X
Inspect control box, associated controls, wiring and connections. X
Check combustion blower housing for lint and debris and clean as necessary. X
Inspect burner assembly ­ clean as needed. X
Inspect heat exchanger ­ clean as needed. X
Inspect flue system—check for proper attachment to the furnace, any dislocated
X
sections, and for signs of corrosion. Replace if necessary.
System:
Inspect airflow system (ductwork)—check for leaks and repair as needed. X
Inspect evaporator coil, drain pan and condensate drain lines as applicable. Clean
X
as needed.

This list may not include all maintenance items, and inspection interval times may vary depending on operational conditions of the furnace.
Ask your servicing dealer for further details about an economical service contract that covers seasonal inspections.
NOTE TO EQUIPMENT OWNER:
For your convenience, please record the model and serial numbers of your new equipment in the spaces
provided. This information, along with the installation data and dealer contact information will be helpful
should your system require maintenance or service.
FURNACE INSTALLATION INFORMATION:
Model # _____________________________________ Date Installed ________________________________
Serial # ______________________________________ DEALERSHIP CONTACT INFORMATION:
AIR CONDITIONER OR HEAT PUMP Company Name_______________________________
Model # _____________________________________ Address______________________________________
Serial # _____________________________________ _____________________________________________
INDOOR COIL (Furnace Coil or Fan Coil) Phone Number _______________________________
Model # _____________________________________ Technician Name _____________________________
Serial # _____________________________________ _____________________________________________
_____________________________________________
NOTE TO INSTALLER:
This manual must be left with the equipment owner.

TO OBTAIN INFORMATION ON PARTS: Consult your installing dealer or classified section of your local telephone directory under the
“Heating Equipment” or “Air Conditioning Contractors & Systems” heading for dealer listing by brand name.
Have available the Model No., Series Letter, & Serial No. of your equipment to ensure correct replacement part.
Copyright 2018 Carrier Corporation Printed in the U.S.A. Edition Date: 05/18 Catalog No: OM58-132
Manufacturer reserves the right to change, at any time, specifications and design without notice and without obligation. Replaces: OM58-131

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