II. CHECK PRESSURE SWITCHES
This control proves operation of the draft inducer. Check switch
operation as follows:
1. Turn off 115-v power to furnace.
2. Remove control access door and disconnect inducer motor
12-pin wire harness at inducer motor.
3. Turn on 115-v power to furnace.
4. Set thermostat to call for heat. When pressure switches are
functioning properly, fault code 42 will flash on control
center approximately 10 sec after thermostat switch is
closed. If either a fault code 31 or 32 is flashed when ICM
inducer motor is disconnected, the furnace will shut itself
down immediately. Determine the reason pressure switches
did not function properly and correct the condition.
5. Turn off 115-v power to furnace.
6. Reconnect inducer motor wire harness. Reinstall furnace
access door.
7. Turn on 115-v power to furnace.
8. Reset thermostat to desired temperature.
CHECKLIST
1. Put away tools and instruments. Clean up debris.
2. Verify manual reset switch has continuity.
3. Verify that blower and control access doors are properly
installed.
4. Cycle test furnace with room thermostat.
5. Check operation of accessories per manufacturer’s instruc-
tions.
6. Review User’s Manual with owner.
7. Leave literature packet near furnace.
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