Filter
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a. Turn off electrical supply before removing blower and
control access doors.
b. Release filter retainer from clip at front of furnace
casing. (See Fig. 4.) For side return, clips may be used
on either or both sides of the furnace.
c. Slide filter out.
d. Clean filters by spraying tap water through filter from
opposite direction of airflow.
e. Rinse and let dry. Oiling or coating of filter is not
recommended or required.
f. Place filter in furnace.
g. Replace blower and control access doors and turn on
electrical supply 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:
The motors have prelubricated sealed bearings and require no
lubrication.
Remember to disconnect the electrical supply before removing
access doors.
Clean as follows:
1. Remove blower access door.
2. Disconnect blower electrical leads from motor. Squeeze
latches to remove connectors from motor. Disconnect green
ground wire from screw. Note location of wires for reas-
sembly.
3. Remove control.
4. Remove screws holding blower assembly to blower deck
and slide blower assembly out of furnace.
5. Mark blower wheel, motor, and motor support in relation to
blower housing before disassembly to ensure proper reas-
sembly.
6. Loosen setscrew(s) holding blower wheel on motor shaft.
7. Remove bolts holding motor and motor mount to blower
housing and slide motor and mount out of housing. Motor
mount belly band need not be removed unless motor is to be
replaced.
CAUTION: The blower wheel should not be dropped or
bent as balance will be affected.
8. Remove blower wheel from housing.
a. Mark cutoff plate location to ensure proper reassembly.
b. Remove screws holding cutoff plate and remove cutoff
plate from housing.
c. Lift blower wheel from housing through opening.
9. Clean blower wheel and motor using a vacuum with soft
brush attachment. Do not remove or disturb balance weights
(clips) on blower wheel blades.
10. Reinstall blower wheel by reversing items 8 a through c. Be
sure wheel is positioned for proper rotation.
11. Reassemble motor and blower by reversing items 4 through
7.
CAUTION: Be sure the motor is properly positioned in
the blower housing. The motor arrow must point in the
direction of airflow through the furnace after the blower
assembly has been reinstalled in the furnace.
12. Reinstall blower assembly in furnace.
13. Reinstall control. If motor has ground wire, be sure it is
connected as before.
14. Connect blower electrical leads to motor. Please note that
connections are polarized for assembly. DO NOT FORCE.
15. If power choke is attached to blower housing, ensure it is
connected in series with black power lead to motor.
C. Cleaning Heat Exchanger
The following steps should be performed by a qualified service
technician:
NOTE: Deposits of soot and carbon indicate the existence of a
problem which needs to be corrected. Take action to correct the
problem.
If it becomes necessary to clean the heat exchanger because of
carbon deposits, soot, etc., proceed as follows:
1. Turn gas and power to furnace to OFF.
2. Remove control and blower access doors.
3. Disconnect wires to the following components. Mark wires
to aid in reconnection of:
TABLE 1—UPFLOW/HORIZONTAL FILTER SIZE INFOR-
MATION (IN.)
FURNACE
CASING WIDTH
FILTER SIZE†
FILTER
TYPE
Side Return Bottom Return
14-3/16 (1) 16 X 25 X 1* (1) 14 X 25 X 1 Cleanable
21 (1) 16 X 25 X 1 (1) 20 X 25 X 1* Cleanable
24-1/2 (2) 16 X 25 X 1* (1) 24 X 25 X 1 Cleanable
* Factory-provided with the furnace.
† Filters may be field modified as required by cutting and folding the frame as
indicated on the filter.
Fig. 4—Upflow/Horizontal Component Identification
A95270
DRAFT
SAFEGUARD
SWITCH
PRESSURE
SWITCHES
FILTER
RETAINER
WASHABLE
FILTER
MOUNTING
SCREWS
MAIN
LIMIT
SWITCH
RELIEF
BOX
MANUAL
RESET
LIMIT
SWITCHES
CONTROL
AIRFLOW
SELECTOR
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