Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Catalog No. 04-53480195-01 Printed in U.S.A. Form 48TC-1SO Pg 8 319 2-19 Replaces: OG-48TC580J-07
© Carrier Corporation 2019
BEFORE YOU CALL FOR SERVICE, CHECK
FOR PROBLEMS THAT CAN BE EASILY
SOLVED
If insufficient heating or cooling is suspected:
( ) 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 these checks do not reveal the
cause, call your servicing dealer.
If your unit is not operating at all, check the following list for
easy solutions:
( ) Check to be sure that your thermostat/unit controller tem-
perature selector is set above the indoor temperature during the
heating season, or below the indoor temperature during the
cooling season. Be sure the SYSTEM switch in the proper
HEAT or COOL position and not in the OFF position.
( ) Is the electrical supply switch ON? Are any fuses blown,
or has the circuit breaker tripped?
( ) During the heating season, check the external manual
shutoff valve. Is this lever parallel with the pipe, indicating that
the valve is open? Or is the lever at the right angle, indicating
that the valve is closed? If closed, has the gas been shut off for
safety reasons? Otherwise, you may open the valve and follow
the start-up procedures listed in this manual.
NOTE: Before proceeding with the next check, turn OFF the elec-
trical power supply to the unit. Remove the gas component access
panel.
( ) During the heating season, check the control switch on
the gas valve. Is it in the ON position? If it is not, be sure it has
not been turned off for the purpose of safety. If no safety haz-
ards are present, follow the start-up procedures in this manual.
If your unit still fails to operate, call your servicing dealer for
troubleshooting and repairs. Specify the model and serial num-
bers of your unit. (Record them in this manual in the space pro-
vided.) If the dealer knows exactly which unit you have, he
may be able to offer suggestions over the phone, or save valu-
able time through knowledgeable preparation for the service
call.
IN CASE OF TROUBLE
If, after performing the above checks, unit performance is un-
satisfactory, shut off the unit and call your dealer.
Dealer’s Name ___________________________________
Telephone No. ____________________________________
Unit Model ______________________________________
Unit Serial Number ________________________________
REGULAR DEALER MAINTENANCE
Heat Exchanger
NOTE: To ensure dependable and efficient heating operation, the
heat exchanger should be checked by a qualified maintenance per-
son before each heating season, and cleaned when necessary.
AUTION
Checking and/or cleaning the heat exchanger involves remov-
ing the gas controls assembly and the flue collector box cover.
When finished, the gas controls must be reinstalled for proper
operation. Also, the flue collector box cover must be replaced
correctly, with “red” RTV, so that a proper seal is maintained.
Contact your dealer for the required periodic maintenance. At
the beginning of each cooling/heating season and as conditions
require.
Fans and Belts, and Fan Motor
Check quarterly the condition of fan wheels and housings, belt
tension and fan motor shaft bearings. No lubrication of condenser
or evaporator fan bearings or motors is required or recommended.
Evaporator and Condenser Coils
Cleaning of the coils should be done by qualified service per-
sonnel. This procedure should be performed prior to cooling
operation or more frequently should conditions require. Con-
tact you dealer for the required annual maintenance.
Condensate Drain
The drain pan and condensate drain line should be checked and
cleaned at the same time the cooling coils are checked by your
dealer.
In addition to the type of routine maintenance you might be
willing to perform, your unit should be inspected regularly by a
properly trained and qualified service technician. An inspec-
tion (preferably each heating/cooling season, but at least every
year) should include the following:
• Inspection of all flue product passages, including the burn-
ers, heat exchanger, and flue collector box.
• Inspection of all combustion and ventilation-air passages
and openings.
• Close inspection of all gas pipes leading to and inside your
unit.
• Inspection and if required, cleaning of the condenser and
evaporator coils.
• Inspection, and if required, cleaning of the condensate
drain pan.
• Inspection and cleaning of blower wheel housing and motor.
• Inspection of all supply and return-air ducts for leaks, ob-
structions, and insulation integrity. Any problems found
should be resolved at the time of inspection.
• Inspection of the unit base for cracks, gaps, etc., which
may cause a hazardous condition.
• Inspection of the unit casing for signs of deterioration.
• Inspection of all electrical wiring and components to en-
sure proper connection.
• Inspection for leaks in the refrigerant circuit. Pressure
check to determine appropriate refrigerant charge.
• Inspection of fan wheels and housings, belt tension, and
fan motor shaft bearings.
• Operational check of the unit to determine working condi-
tions. Repair or adjustment should be made at the time of
inspection.
Your servicing dealer may offer an economical service contract
that covers seasonal inspections. Ask for further details.
Complete service instructions can be found in the unit’s Ser-
vice and Maintenance Instructions.
CAUTION
EQUIPMENT DAMAGE HAZARD
Failure to follow this caution may result in damage to
equipment.
This checkout should not be attempted by anyone not having
the required expertise and equipment to do the job properly.