Carrier 48JC04-06, Service And Maintenance Instructions

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Fig. 45 — Heat Exchanger Assembly
To inspect blower wheel, shine a flashlight into draft hood
opening. If cleaning is required, remove motor and wheel as
follows:
1. Remove the screw at the base of the burner partition panel
(see Fig. 47) and slide out the panel.
2. Remove the seven screws attaching the induced-draft
motor housing to the vestibule plate. (See Fig. 45.)
3. The blower wheel can be cleaned at this point. If addi -
tional cleaning is required, continue with Steps 4 and 5.
4. Remove the blower from the motor shaft by removing two
setscrews.
5. Removing motor: remove the four screws holding the
motor to the mounting plate. Remove the motor cooling
fan by removing one setscrew. Remove nuts that hold the
motor to the mounting plate.
6. Reverse the procedure outlined above to reinstall the motor.
Burners and Igniters
MAIN BURNERS
To access burners, remove burner access panel and slide out
burner partition. At the beginning of each heating season,
inspect for deterioration or blockage due to corrosion or other
causes. Observe the main burner flames and adjust, if
necessary.
Orifice projection
Refer to Fig. 46 for maximum projection dimension for orifice
face to manifold tube.
Fig. 46 — Orifice Projection
REMOVAL AND REPLACEMENT OF GAS TRAIN
See Fig. 41, 45, 47, and 48.
1. Shut off manual gas valve.
2. Shut off power to unit.
3. Remove the control box access panel.
4. Remove the control box high voltage cover.
5. Remove the screw at the base of the burner partition panel
(see Fig. 47) and slide out the panel.
6. Disconnect gas piping at unit gas valve.
7. Remove wires connected to gas valve. Mark each wire.
8. Remove igniter wires and sensor wires at the Integrated
Gas Unit Controller (IGC). (See Fig. 49.)
9. Remove the two screws attaching the burner rack to the
vestibule plate (see Fig. 45).
10. Slide the burner tray out of the unit (see Fig. 48).
11. Reverse the procedures outlined above to reinstall the
burner rack.
HEATER TUBE
ASSEMBLY
SEAL STRIPS,
SPONGE RUBBER
REGULATOR
GASKET
REGULATOR
BAFFLE ASSEMBLY
(LOW NOx ONLY)
RETAINER
FLUE COVER
ASSEMBLY
BURNER ASSEMBLY
INDUCER FAN-MOTOR
ASSEMBLY
FLUE BAFFLE
(LOW NOx ONLY)
VESTIBULE
PLATE
PRESSURE SWITCH
HOSE CONNECTION
CAUTION
EQUIPMENT DAMAGE HAZARD
Failure to follow this CAUTION can result in premature
wear and damage to equipment.
When working on gas train, do not hit or plug orifice spuds.
ORIFICE
1.00-in
(25.4 mm)
MANIFOLD
PIPE