Cleaning Burners - Bryant 352MAV Service And Maintenance Procedures Manual

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. Disconnect
capacitor and ground wire attached to blower housing
before removing motor.
f. Remove blower wheel from housing.
CAUTION: The blower wheel should not be dropped or
bent as balance will be affected.
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 control box, transformer, and door switch assem-
bly on blower shelf.
12. 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)
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.
NOTE: Refer to Table 1 for motor speed lead relocation if leads
were not identified before disconnection.
TABLE 1—SPEED SELECTION
COLOR SPEED
White Common
Black High
Yellow Med-High
Orange† Med
Blue Med-Low
Red Low*
* Continuous blower speed.
† Available on 5-speed blowers only.
CAUTION: Heating air speed selection MUST be ad-
justed to provide proper temperature rise as specified on
the rating plate. Failure to adjust the heating speed may
shorten heat exchanger life.
c. Connect field drain to condensate trap.
NOTE: Ensure tubes are not kinked or pinched, as this will affect
operation.
AS SHIPPED
C
OM
Cool
SPARE
High-Gas Heat
Spare/High-Gas Heat
Low-Gas Heat
—4—
13. Reconnect wires.
Refer to furnace wiring diagram and connect thermostat leads if
previously disconnected. (See Fig. 15.)
14. Turn on electrical supply. Manually close blower access
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-W/W1, R-to-
W/W1-and-W2 and then R-to-Y/Y2 on control thermostat
terminals. (See Fig. 11.)
WARNING: Blower access door switch opens 115-v
power to control. No component operation can occur.
Caution must be taken when manually closing this switch
for service purposes. Failure to follow this warning could
result in personal injury or death.
15. If furnace is operating properly, release blower access door
switch, replace blower access door, and replace main
furnace door.
III. CLEANING BURNERS
The following items should be performed by a qualified service
technician. If the burners develop an accumulation of light dirt or
dust, they may be cleaned by using the following procedure:
1. Turn off gas and electrical supplies to furnace.
2. Remove main furnace door.
3. Remove burner box cover.
CELL
PANEL
MANIFOLD
MOUNTING
SCREW
Fig. 5—Burner Box Assembly
4. Using backup wrench, disconnect gas supply pipe from gas
valve.
CAUTION: Label all wires prior to disconnection when
servicing controls. Wiring errors can cause improper and
dangerous operation.
5. Remove wires from gas valve. Note location for reassem-
bly.
6. Remove burner box pressure tube from gas valve regulator
fitting.
7. Remove screws that secure manifold to burner box. (See
Fig. 5.)
MANIFOLD
GAS VALVE
REGULATOR
FITTING
GAS VALVE
A96304