WARNING: Never operate unit without a filter or with filter access door removed. A failure to follow this warning could
result in fire, personal injury, or death.
1. Downflow/Horizontal
Each furnace requires 2 filters which are installed in the return-air duct. (See Fig. 4 and 5.) To remove filters for cleaning or replacement,
proceed as follows:
a. Disconnect electrical power before removing blower access door.
b. Remove screw from front of door and remove blower access door.
c. Reach up behind top plate, tilt filters toward center of return-air plenum, remove filters, and clean or replace as needed. Replace if torn
or if filter is disposable type.
d. If furnaces are equipped with permanent, washable filters, clean filters with tap water. Spray water through filter in opposite direction
of airflow.
e. Rinse and let dry. Oiling or coating of filters is not recommended or required.
f. Reinstall filters.
g. Replace blower access door.
h. Restore electrical power to furnace.
2. Upflow
Each furnace requires 1 or 2 filters which are installed in the blower compartment. (See Fig. 6.) To remove filters for cleaning or
replacement, proceed as follows:
a. Disconnect electrical power before removing access doors.
b. Remove blower and control access doors.
c. Release filter retainer from clip at front of furnace casing. (See Fig. 6.) For side return, clips may be used on either or both sides of the
furnace.
d. Slide filter(s) out.
e. Replace filter if torn or disposable type. If furnace is equipped with permanent, washable filters. Clean filters with tap water. Spray water
through filter in opposite direction of airflow.
f. Rinse and let dry. Oiling or coating of filter is not recommended or required.
g. Reinstall filter(s).
h. Replace blower and control access doors.
i. Restore electrical power to furnace.
B.
Blower Motor and Wheel
For long life, economy, and high efficiency, clean accumulated dirt and grease from the blower wheel and motor annually.
The following steps should be performed by a qualified service technician.
Some motors have prelubricated sealed bearings and require no lubrication. These motors can be identified by the absence of oil ports on each
end of the motor. For those motors with oil ports, lubricate motor every 5 years if motor is used on intermittent operation (thermostat FAN in
AUTO mode), or every 2 years if motor is in continuous operation (thermostat FAN in ON mode).
NOTE:
Remember to disconnect the electrical supply before removing access doors.
Table 1—Filter Size Information for Downflow/Horizontal Furnaces (In.)
FURNACE
CASING WIDTH
FILTER QUANTITY
AND SIZE
14-3/16
(2) 14 X 20 X 1
17-1/2
(2) 14 X 20 X 1
21
(2) 16 X 20 X 1
24-1/2
(2) 16 X 20 X 1
Table 2—Filter Size Information for Upflow Furnaces (In.)
FURNACE
CASING WIDTH
FILTER QUANTITY AND SIZE
Side Return
Bottom Return
14-3/16
(1) 16 X 25 X 1
(1) 14 X 25 X 1
17-1/2
(1) 16 X 25 X 1
(1) 16 X 25 X 1
21
(1) 16 X 25 X 1
(1) 20 X 25 X 1
24-1/2
(2) 16 X 25 X 1
(1) 24 X 29 X 1
—3—
