Cooling Sequence Of Operation - Lennox G43UF SERIES Unit Information

COOLING SEQUENCE OF OPERATION

NORMAL COOLING MODE
POWER ON
IGNITION CONTROL MAIN POWER ON.
CONTROL SELF DIAGNOSTIC CHECK.
IS CONTROL OPERATING NORMALLY?
YES
IS POLARITY REVERSED?
NO
IS VOLTAGE
HIGH ENOUGH?
75 VOLTS
YES
ROLLOUT SWITCH MONITORED CONTINUOUSLY.
IS ROLLOUT SWITCH CLOSED?
YES
CHECK FOR MAIN BURNER FLAME SENSE.
IS MAIN BURNER FLAME OFF?
YES
LED: SLOW FLASH RATE REMAINS UNCHANGED
THROUGHOUT COOLING CYCLE.
THERMOSTAT CALLS FOR COOLING.
COMPRESSOR CONTACTOR AND SYSTEM FAN
ENERGIZED ON COOLING SPEED.
ELECTRONIC AIR CLEANER ENERGIZED.
THERMOSTAT OPENS.
COMPRESSOR OFF.
SYSTEM FAN OFF
WITH 0-SECOND DELAY. ELECTRONIC
AIR CLEANER DE−ENERGIZED.
SureLight Control Board 32M88
NO
YES
NO
NO
SEQUENCE HOLDS UNTIL ROLLOUT SWITCH CLOSES.
NO
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ABNORMAL COOLING MODE
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.
SIGNAL POLARITY REVERSED AT LED.
LED SIGNALS WAITING ON CALL FROM
THERMOSTAT. CONTROL WILL NOT RESPOND
UNTIL VOLTAGE RISES ABOVE 75 VOLTS.
GAS VALVE OFF. COMBUSTION AIR INDUCER ON.
INDOOR BLOWER ON.
SIGNAL ROLL-OUT SWITCH OPEN AT LED.
GAS VALVE OFF. COMBUSTION AIR INDUCER OFF.
INDOOR BLOWER OFF WITH NORMAL DELAY.
SIGNAL UNWANTED FLAME SENSED AT LED.
SEQUENCE HOLDS UNTIL FLAME IS NOT SENSED.