915SB: Installation, Start-up, Operating and Service and Maintenance Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
57
To ensure long life, economy, and high efficiency, clean accumulated
dirt and grease from blower wheel and motor annually.
The inducer and blower motors are pre-lubricated and require no
additional lubrication. These motors can be identified by the absence of
oil ports on each end of the motor.
The following items should be performed by a qualified service
technician. Clean blower motor and wheel as follows:
1. Turn off electrical supply to furnace.
2. Remove blower door.
3. All factory wires can be left connected, but field thermostat and
accessory wiring may need to be disconnected depending on their
length and routing.
4. If the vent and combustion air pipe passes through the blower
compartment, it will be necessary to remove the pipes from the
blower compartment.
Disconnect the vent and combustion air pipe by:
a. Loosen the clamps on the vent couplings and combustion air
pipe external to the furnace.
b. Separate the pipes from the couplings and move them aside.
c. Loosen the clamps on the vent couplings and combustion air pipe
located on the blower shelf.
d. Separate the pipes from the blower compartment and set aside.
e. Remove the couplings from the pipe adapters and set aside.
f. After servicing the blower, reverse steps a through e.
g. Tighten all clamps 15 lb -in.
See
for steps 5 through 14.
5. Remove screws securing blower assembly to blower shelf and slide
blower assembly out of furnace. Detach ground wire and
disconnect blower motor harness plugs from blower motor.
NOTE:
Blower wheel is fragile. Use care.
NOTE:
On 66100E21 size, the top screw securing blower to shelf must
be removed in order to remove the blower. (See
6. Clean blower wheel and motor by using a vacuum with soft brush
attachment. Be careful not to disturb balance weights (clips) on
blower wheel vanes. Do not bend wheel or blades as balance will be
affected.
7. If greasy residue is present on blower wheel, remove wheel from
the blower housing and wash it with an appropriate degreaser. To
remove wheel:
NOTE:
The DIBC composite wheel used in some models should be
cleaned with mild soapy water only. Allow wheel to dry prior to
reassembly.
a. Mark blower wheel location on shaft before disassembly to
ensure proper reassembly.
b. Loosen setscrew holding blower wheel on motor shaft.
NOTE:
Mark blower mounting arms and blower housing so each arm is
positioned at the same hole location during reassembly.
c. Mark blower wheel orientation and cutoff plate location to
ensure proper reassembly.
d. Remove screws securing cutoff plate and remove cutoff plate
from housing.
e. Remove bolts holding motor mounts to blower housing and slide
motor and mounts out of housing.
f. Remove blower wheel from housing.
g. Clean wheel per instructions on degreaser cleaner. Do not get
degreaser in motor.
8. Reassemble motor and blower wheel by reversing items 7b through
7f. Ensure wheel is positioned for proper rotation.
9. Torque motor mounting bolts to 40 +/- 10 lb-in. when reassembling.
NOTE:
Ensure that the removable inlet ring is installed before the
motor on furnaces with a DIBC composite blower.
10. Torque blower wheel set screw to 160 +/- 20 lb-in. when
reassembling.
11. Verify that blower wheel is centered in blower housing and set
screw contacts the flat portion of the motor shaft. Loosen set screw
on blower wheel and reposition if necessary.
A190094B
Fig. 65 – Blower Assembly on
30040E14 and 36060E14
A190407
Fig. 66 – Blower Assembly on
66100E21
TORQUE THE BLOWER
WHEEL SET SCREW
160 LB-IN +/- 20 LB-IN.
BLOWER INLET
ORIFICE
BLOWER MOTOR
BLOWER WHEEL SET-SCREW
SHALL BE TIGHTENED TO
160 IN.-LB. +/-20 IN. -LB.
MOTOR SHAFT FLAT
BLOWER
WHEEL
HUB
GROMMET
MOTOR
ARM
WASHER
SCREW
BRACKET
BLO HSG ASSY
BRACKET, BLO MTG (LEFT)
SCREW (2)
ENSURE THAT
WRAPPER IS OVER
TAB ON EACH SIDE
BRACKET, BLO MTG (RIGHT)
BLOWER MOTOR
SCREW
SCREW
LOCATIONS
BLO HSG ASSY
SCREW (3)
SCREW (3)
SCREW
COLLAR