Blower Motor And Wheel Maintenance - Bryant 355MAV Service And Maintenance Procedures Manual

Fig. 3—Bottom Filter Arrangement
8. Replace blower access panel and main furnace door.
9. Turn on electrical supply to furnace.
NOTE: If the filter has cross-mesh binding, the binding must face
the blower. If the filter has an air direction arrow, the arrow must
point toward the blower.
II. BLOWER MOTOR AND WHEEL MAINTENANCE
To ensure long life, economy, and high efficiency, clean accumu-
lated 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 main furnace door and blower access panel.
3. Disconnect wires.
a. Disconnect motor wiring harness plug on blower hous-
ing.
b. Disconnect auxiliary limit switch leads at switch.
c. Disconnect field thermostat connections depending on
their length and routing.
4. Position control box, transformer, and door switch assembly
to right side of furnace casing.
5. If condensate trap is located in left- or right-hand side of
furnace casing, proceed to item 6, otherwise remove trap
and tubing as described below.
a. Disconnect field drain connection from condensate trap.
b. Disconnect drain and relief port tubes from condensate
trap.
c. Remove condensate trap from blower shelf.
6. Remove screws securing blower assembly to blower shelf
and slide blower assembly out of furnace.
7. 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.
8. If greasy residue is present on blower wheel, remove wheel
from the blower housing and wash it with an appropriate
degreaser. To remove wheel:
a. Mark blower wheel location on shaft before disassembly
to ensure proper reassembly.
WASHABLE
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Fig. 4—Filter Installed for Side Inlet
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.
9. Reassemble motor and blower wheel by reversing items 8b
through 8f. Ensure wheel is positioned for proper rotation.
10. Reinstall blower assembly in furnace.
11. Reinstall condensate trap and tubing if previously removed.
a. Reinstall condensate trap in hole in blower shelf.
b. Connect condensate trap drain tubes. See Fig. 8 or tubing
diagram on main furnace door for proper tube location.
(1.) Connect 1 tube (blue or blue and white striped)
(2.) Connect 1 tube (violet or unmarked) from inducer
(3.) Connect 1 tube (relief port, green or pink) from
c. Connect field drain to condensate trap.
NOTE: Ensure tubes are not kinked or pinched, as this will affect
operation.
12. Reinstall control box, transformer, and door switch assem-
bly on blower shelf.
13. Reconnect wires.
a. Refer to furnace wiring diagram, and connect motor and
auxiliary limit switch leads. (See Fig. 17.)
b. Connect thermostat leads if previously disconnected.
14. Turn on electrical supply. Manually close blower access
panel door switch. Use a piece of tape to hold switch closed.
Check for proper rotation and speed changes between
heating and cooling by jumpering R to G and R to Y on
control center thermostat terminals. (See Fig. 12.)
—3—
FILTER
from collector box.
housing.
collector box.
FILTER
RETAINER
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