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Troubleshooting: Cooling Sequence of Operation
COOLING SEQUENCE OF OPERATION
NORMAL COOLING MODE
ABNORMAL COOLING MODE
IGNITION CONTROL MAIN POWER ON.
CONTROL SELF DIAGNOSTIC CHECK.
IS CONTROL OPERATING NORMALLY?
YES
LED FLASHES CODE 1 POLARITY REVERSED
CONTROL WILL CONTINUE TO CALL FOR COOLING IN
THIS CONDITION.
POWER ON
GAS VALVE OFF. COMBUSTION AIR INDUCER OFF.
INDOOR BLOWER OFF WITH NORMAL DELAY.
SIGNAL CIRCUIT BOARD FAILURE AT LED.
INTERRUPT MAIN POWER TO RESET CONTROL.
YES
IS POLARITY CORRECT?
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). EAC TERM. ENERGIZED.
COMPRESSOR OFF.
THERMOSTAT OPENS.
SYSTEM FAN AND EAC TERM. OFF
WITH 45‐SECOND DELAY.
NO
NO
LED FLASHES CODE 8 ROLLOUT SWITCH OPEN. GAS
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.
IS VOLTAGE
ABOVE 70 VOLTS?
LED FLASHES CODE 13 LOW VOLTAGE. CONTROL
WILL CONTINUE TO CALL FOR COOLING
IN THIS CONDITION.
YES
YES
NO
NO
IS THERE A PROPER GROUND?
YES
NO
LED FLASHES CODE 2 IMPROPER GROUND
CONTROL WILL CONTINUE TO CALL FOR COOLING
IN THIS CONDITION.
