6
MAINTAINING YOUR UNIT
All maintenance should be handled by skilled, experienced
personnel. Your dealer can help establish a standard procedure.
For your safety, keep the gas heating area clear and free of
combustible materials, gasoline, and other flammable liquids
and vapors.
To ensure proper functioning of the unit, flow of combustion and
ventilating air must not be obstructed from reaching the gas heat-
ing area. Clearance of at least 4 ft on all sides is required.
ROUTINE MAINTENANCE AND CARE
FOR THE EQUIPMENT OWNER
Before proceeding with those things you might want to main-
tain yourself, please carefully consider the following:
Air Filters
Air filters should be checked at least every 3 or 4 weeks and
changed or cleaned whenever they become dirty. Table 1 indi-
cates the correct filter size for your unit. Open the hinged filter
access door to replace or inspect the filters. All units have filter
tracks into which the filters slide. Remove the filters by pulling
outward from the track. See Fig. 4 for filter access door loca-
tion. Note the direction of flow arrows on filter frame.
Table 1 — Indoor-Air Filter Data*
If you have difficulty in locating your air filter in the return-air
duct system, or if you have questions concerning proper filter
maintenance, contact your dealer for instructions.
When replacing your unit filters, always use the same size and
type of filter that was originally supplied by the installer.
Units with outdoor air capability have a cleanable filter for the
outdoor air. This filter should be checked annually and cleaned
as necessary. Remove by removing screws in outdoor-air filter
retainer and sliding filters out of the unit.
Heat Exchanger
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.
This checkout should not be attempted by anyone not having
the required expertise and equipment to do the job properly.
Checking and/or cleaning the heat exchanger involves remov-
ing the gas controls assembly and the flue collector box cover
and, when completed, reinstalling the gas controls assembly
for proper operation. Also, the flue collector box cover must be
replaced correctly so that a proper seal is maintained. Contact
your dealer for the required periodic maintenance.
Fan and Belts
Periodically check the condition of fan wheels and housings
and belt tension. When service is necessary, call your dealer.
Evaporator-Fan Motor, Condenser-Fan Motor
and Combustion-Fan Motor
Lubrication is not recommended. Bearings will not require lu-
brication for at least 5 years of normal operation. After 5 years,
motor life can be extended by having the motors serviced at an
authorized motor service shop.
Fan Shaft Bearings
Charge fittings annually with Shell Alvania No. 2 or equivalent
grease.
Evaporator and Condenser Coils
Cleaning of the coils should only be done by qualified service
personnel. Contact your dealer for the required maintenance as
needed.
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.
Compressors
All compressors are factory shipped with a normal charge of
the correct type refrigeration grade oil in them and should rare-
ly require additional oil. The service technician must be certain
the proper oil level is maintained in the compressor when it is
installed and running.
WARNING
1. TURN OFF GAS SUPPLY AND THEN ELECTRICAL
POWER TO YOUR UNIT BEFORE SERVICING OR
PERFORMING MAINTENANCE.
2. Do not turn off electrical power to this unit without first
turning off the gas supply.
3. When removing access panels or performing mainte-
nance functions inside your unit, be aware of sharp sheet
metal parts and screws. Although special care has been
taken to reduce sharp edges inside the unit, be extremely
careful when handling parts or reaching into the unit.
Failure to follow these procedures can result in serious fire
or personal injury.
48P UNIT
SIZE
FILTER TYPE
QUANTITY...Size
(in.)
030-050
Disposable Fiberglass
(Standard) or Medium Efficiency
30% Pleated (Optional)
8...20 x 25 x 2,
8...20 x 20 x 2
90% Bag (Optional) with High-
Velocity Pre-Filters
6...20 x 24 x 22,
6...20 x 20 x 22,
12...16 x 20 x 2,
3...20 x 24 x 2
055-070
Disposable Fiberglass
(Standard) or Medium Efficiency
30% Pleated (Optional)
12...20 x 25 x 2,
12...20 x 25 x 2
90% Bag (Optional) with High-
Velocity Pre-Filters
6...24 x 24 x 22,
6...24 x 20 x 22,
6...24 x 24 x 2,
6...20 x 24 x 2
075
Disposable Fiberglass
(Standard) or Medium Efficiency
30% Pleated (Optional)
12...20 x 25 x 2,
12...20 x 20 x 2
High Efficiency 65% Pleated
(Optional)
12...20 x 25 x 2,
12...20 x 20 x 2
090,100
Disposable Fiberglass
(Standard) or Medium Efficiency
30% Pleated (Optional)
12...20 x 25 x 2,
12...20 x 20 x 2
High Efficiency 65% Pleated
(Optional)
12...20 x 25 x 2,
12...20 x 20 x 2
*See base unit Installation Instructions if field-supplied or optional
factory-supplied filters are used. When replacing filters, always use
the same type and size originally supplied.
WARNING
Never operate your unit without filters in place. Failure to
heed this warning may result in damage to the blower motor
and/or compressor. An accumulation of dust and lint on inter-
nal parts of your unit can cause loss of efficiency and, in some
cases, fire.
