21-40-01
99M90
Page: 8-8
Issued: May 9, 2012
Rev. New
I-Series Combustion Heater
Owners Manual
8.7
Ventilating Air Blower Maintenance
A. Removal: (See Figure 8.4)
1.
If the heater is equipped with an adapter and screen assembly, remove it from the blower
housing by removing the three screws and lockwashers.
2.
Loosen the four screws and rotate the blower and motor housing to disengage the notched
end from the four screws in the end of the heater jacket. Remove the grommet and separate
the two electrical quick disconnects after sliding back the insulator sleeves on the wire ends.
3.
To remove the motor from the housing, first loosen the Allen head set screw. Remove the fan.
(May require penetrating oil to loosen the fan from the shaft.) Loosen the screw from the
motor bracket in the housing.
4.
Carefully remove the wiring through the motor bracket grommets, note positioning. Remove
the motor.
5.
Remove the screw, nut and flat washer, in the upper corner of the motor bracket assembly.
Remove the two screws, flat washers, and new grommets at the two lower edges securing the
motor bracket assembly. Remove bracket.
B. Inspection:
1.
Inspect the housing and bracket for cracks, corrosion, and damage. Inspect the blower wheel
for broken or bent vanes and replace it for either condition.
C. Installation: (See Figure 8.4)
1.
Insert the ventilating air motor into the motor bracket assembly slide the blower wheel on the
end of motor shaft and rotate it until the set screw is aligned with the flat side of the motor
shaft. Tighten the set screw just tight enough to hold it at this time.
2.
Attach the capacitor and leads assembly to the motor bracket with the screw and lock
washer. Make sure a good electrical ground connection is made at this point.
3.
Insert this assembly into the blower housing and position it so the long screw is in alignment
with the gap on the inner ring of the motor bracket assembly. This is the screw used to
secure and align the motor in the bracket.
4.
Slide the flat washer and rubber washer into position between the legs of the motor bracket
and blower housing.
5.
Make sure all four wires are routed and grommeted as they were prior to disassembly and install
the two screws, flat washers and new grommets at the two lower edges securing the motor
bracket assembly. Then install the grommet, flat washer, nut, and screw in the remaining
upper corner of the motor bracket assembly.
6
Center the motor bracket in the housing and tighten the screw to secure it. The motor should
be positioned in the bracket to locate the blower wheel properly in the blower housing. The
blower wheel should be positioned so it will rotate freely and just clear the contoured spill
plate in the blower housing. Tighten the Allen head set screw, and spin the blower wheel
by hand for a clearance check. Then apply appropriate voltage to run the motor as a final
clearance check.
7.
Attach the adapter and screen assembly (if used) to the end of blower housing with three
screws and lockwashers.
