Bryant 355MAV - Manual (Page 4)

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.
All factory wires can be left connected, but field thermostat
connections may need to be disconnected 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 (See Fig. 5.):
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. Detach ground
wire and disconnect blower motor harness plugs from
blower motor.
NOTE: Blower wheel is fragile. Use care.
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.
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.
9. Reassemble motor and blower wheel by reversing items 8b
through 8f. Ensure wheel is positioned for proper rotation.
Be sure to attach ground wire and reconnect blower harness
plugs to blower motor.
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. 5 or tubing
diagram on main furnace door for proper tube location.
(1.) Connect 1 tube (blue or blue and white striped)
from collector box.
(2.) Connect 1 tube (violet or unmarked) from inducer
housing.
(3.) Connect 1 tube (relief port, green or pink) from
collector box.
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 thermosta
leads if previously disconnected. (See Fig. 17.)
WARNING: ELECTRICAL SHOCK HAZARD
Failure to follow this warning could result in personal
injury or death.
Blower access panel door switch opens 115-v power to
furnace control. No component operation can occur.
Caution must be taken when manually closing this switch
for service purposes.
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/Y2 on
furnace control thermostat terminals. (See Fig. 12.)
15. If furnace is operating properly, release blower access panel
door switch, replace blower access panel, and replace main
furnace door.
Fig. 5—Factory-Shipped Upflow Tube
Configuration
(Shown with Blower Access Panel Removed)
A01030
COLLECTOR BOX
TUBE (PINK)
COLLECTOR BOX
TUBE (GREEN)
INDUCER HOUSING
(MOLDED) DRAIN
TUBE (BEHIND
COLLECTOR BOX
DRAIN TUBE)
COLLECTOR BOX
DRAIN TUBE (BLUE)
FIELD-INSTALLED
FACTORY-SUPPLIED
DRAIN TUBE
COUPLING (LEFT
DRAIN OPTION)
FIELD-INSTALLED
FACTORY-SUPPLIED
DRAIN TUBE
FIELD-INSTALLED
FACTORY-SUPPLIED
1 ⁄
2 -IN. CPVC STREET
ELBOWS (2) FOR
LEFT DRAIN OPTION
FIELD-INSTALLED
FACTORY-SUPPLIED
DRAIN TUBE
COUPLING (RIGHT
DRAIN OPTION)
CAP
COLLECTOR BOX
DRAIN TUBE (BLUE
& WHITE STRIPED)
PLUG
CONDENSATE
TRAP
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