Fig. 4—Model 394HAD Upflow
Fig. 5—Model 396HAD Downflow
b. Remove blower and control access doors.
3. Disconnect wires from auxiliary limit on blower housing
(downflow furnace only).
c. Release filter retainer from clip at front of furnace
casing. (See Fig. 4.) For side return, clips may be used on
4. Remove control box.
either or both sides of the furnace.
5. Remove electrical leads from numbered side of blower
d. Slide filter out.
speed selector. (See Fig. 4 and 5.) Note location of wires for
e. Furnaces are equipped with permanent, washable filters.
Clean filters with tap water. Spray water through filter in
6. Remove screws holding blower assembly to blower deck
opposite direction of airflow.
and slide blower assembly out of furnace.
f. Rinse and let dry. Oiling or coating of filter is not
7. Squeeze side tabs of blower speed selector and pull it out of
recommended or required.
g. Reinstall filter.
8. Loosen screw in strap holding motor capacitor to blower
h. Replace access doors.
housing and slide capacitor out from under strap.
i. Restore electrical power to furnace.
9. Mark blower wheel, motor, and motor support in relation to
blower housing before disassembly to ensure proper reas-
B. Blower Motor and Wheel
For long life, economy, and high efficiency, clean accumulated dirt
10. Loosen setscrew holding blower wheel on motor shaft.
and grease from the blower wheel and motor annually.
11. Remove bolts holding motor mount to blower housing and
The following steps should be performed by a qualified service
slide motor and mount out of housing. Disconnect ground
wire attached to blower housing before removing motor.
Some motors have prelubricated sealed bearings and require no
lubrication. These motors can be identified by the absence of oil
12. Lubricate motor (when oil ports are provided).
ports on each end of the motor. For those motors with oil ports,
a. Remove dust caps or plugs from oil ports located at each
lubricate motor every 5 years if motor is used on intermittent
end of motor.
operation (thermostat FAN switch in AUTO position), or every 2
b. Use a good grade of SAE 20 nondetergent motor oil and
years if motor is in continuous operation (thermostat FAN switch
put 1 teaspoon, 5 cc, 3/16 oz, or 16 to 25 drops in each
in ON position).
oil port. Do not over-oil.
Remember to disconnect the electrical supply before removing
c. Allow time for total quantity of oil to be absorbed by
Clean and lubricate as follows:
d. Wipe excess oil from motor housing.
1. Remove 2 screws from blower access door (downflow
e. Replace dust caps or plugs on oil ports.
furnace only). Remove blower access door.
13. Remove blower wheel from housing.
2. Remove vent pipe enclosure (downflow furnace only) and
disconnect short piece of vent pipe from relief box.
a. Mark cutoff location to ensure proper reassembly.