Troubleshooting: Cooling Sequence Of Operation - COMFORT-AIRE Century GUH80C Series Service Manual

Troubleshooting: Cooling Sequence of Operation

N O R M
IGNITION CONTROL MAIN POWER ON.
CONTROL SELF DIAGNOSTIC CHECK.
IS CONTROL OPERATING NORMALLY?
IS THERE A PROPER GROUND?
IS POLARITY CORRECT?
ABOVE 70 VOLTS?
ROLLOUT SWITCH MONITORED CONTINUOUSLY.
IS ROLLOUT SWITCH CLOSED?
LED: SLOW FLASH RATE REMAINS UNCHANGED
THROUGHOUT COOLING CYCLE.
THERMOSTAT CALLS FOR COOLING.
COMPRESSOR CONTACTOR AND SYSTEM FAN
ENERGIZED WITH 2 SECOND DELAY
(COOLING SPEED)
THERMOSTAT OPENS.
COMPRESSOR OFF.
SYSTEM FAN AND EAC TERM. OFF
WITH 45 SECOND DELAY.
508096-01
COOLING SEQUENCE OF OPERATION
A L C O O L N I G M O D E
POWER ON
YES
YES
YES
IS VOLTAGE
YES
YES
A B
LED FLASHES STEADY - CIRCUIT BOARD FAILURE
NO
GAS VALVE OFF. COMBUSTION AIR INDUCER OFF.
INDOOR BLOWER OFF WITH NORMAL DELAY.
INTERRUPT MAIN POWER TO RESET CONTROL.
NO
LED FLASHES CODE 2 IMPROPER GROUND
CONTROL WILL CONTINUE TO CALL FOR COOLING
NO
LED FLASHES CODE 1 POLARITY REVERSED
CONTROL WILL CONTINUE TO CALL FOR COOLING IN
NO
LED FLASHES CODE 13 LOW VOLTAGE. CONTROL
WILL CONTINUE TO CALL FOR COOLING
LED FLASHES CODE 8 ROLLOUT SWITCH OPEN. GAS
NO
VALVE OFF. COMBUSTION AIR INDUCER ON. INDOOR
BLOWER ON. SEQUENCE HOLDS UNTIL ROLLOUT SWITCH
CLOSES AND MAIN POWER IS INTERRUPTED OR
THERMOSTAT IS CYCLED OFF/ON FOR 1 SEC. MINIMUM.
Issue 2037
N O R M A L C O O L N I G M O
IN THIS CONDITION.
THIS CONDITION.
IN THIS CONDITION.
D E
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