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Table 1 — Indoor-Air Filter Data
UNIT SIZE
48HX
030,036
048,060
Filter Size
24 x 24
24 x 30
Never operate your unit without filter(s) in place. Fail-
ure to heed this warning may result in damage to the
blower motor and/or compressor. An accumulation of
dust and lint on internal parts of your unit can cause
loss of efficiency and, in some cases, fire.
Heat Exchanger —
To ensure dependable and efficient
heating operation, the heat exchanger should be checked by
a qualified maintenance person before each heating season,
and cleaned when necessary. This checkout should not be
attempted by anyone not having the required expertise and
equipment to properly do the job. Checking and/or cleaning
the heat exchanger involves removing the gas controls as-
sembly and the flue collector box cover and, when com-
pleted, reinstalling the gas controls assembly for proper op-
eration. 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.
Fans and Fan Motor —
Periodically check the con-
dition of fan wheels and housings and fan-motor shaft
bearings. No lubrication of outdoor- or indoor-fan bearings
or motors is required or recommended.
Indoor and Outdoor Coils —
Cleaning of the coils
should only be done by qualified service personnel. Contact
your 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.
Compressor —
All compressors are factory-shipped with
a normal charge of the correct type refrigeration grade oil
and should rarely require additional oil. The service person
must be certain the proper oil level is maintained in the com-
pressor when it is installed and running.
Outdoor Fan
Do not poke sticks, screwdrivers, or any other object
into revolving fan blades. Severe bodily injury may
result.
The fan must be kept free of all obstructions to en-
sure proper cooling. Contact your dealer for any required
service.
Electrical Controls and Wiring —
Electrical con-
trols are difficult to check without proper instrumentation;
therefore, if there are any discrepancies in the operating cycle,
contact your dealer and request service.
Refrigerant Circuit —
The refrigerant circuit is diffi-
cult to check for leaks without the proper equipment; there-
fore, if inadequate cooling is suspected, contact your local
dealer for service.
Combustion Area and Vent System —
The com-
bustion area and vent system should be inspected visually
before each heating season. The normal accumulation of dirt,
soot, rust, and scale can result in loss of efficiency and im-
proper performance if allowed to build up.
If your unit makes an especially loud noise when the
main burners are ignited, shut down the gas heating sec-
tion and call your dealer.
Proceed as follows to inspect the combustion area and power-
venting system of your unit.
1. Turn off electrical power and gas supply to your unit.
2. Remove burner access panel. (See Fig. 2.)
3. Using a flashlight, carefully inspect the burner areas for
dirt, soot, rust, or scale. See Fig. 3.
If dirt, soot, rust, or scale accumulations are found,
call your dealer and do not operate your heating sec-
tion.
4. When you have completed your inspection, follow the
start-up procedures in this manual to restore your unit to
operation.
5. Observe unit heating and emergency heating operations.
Components in heat section may be hot after unit
has been started up. When observing flame, be care-
ful not to get close to or touch heating components
or serious personal injury may result.
Watch the burner flame to see if it is bright blue. If you
observe a suspected malfunction or if the burner flames
are not bright blue, call your dealer.
6. Replace burner access panel.
BURNERS
GAS VALVE
FLUE HOOD
Fig. 3 — Gas Heat Section Detail
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