Sequence Of Operation - Lennox G40UH Series Installation Instructions Manual

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HEATING SEQUENCE OF OPERATION
NORMAL HEATING MODE
ABNORMAL HEATING MODE
I POWER ON ]
CONTROL SELF-CHECK OKAY?
YES !
IS POLARITY CORRECT?
YES !
IS THERE A PROPER GROUND?
YES l
NO
IS VOLTAGE
ABOVE 90 VOLTS?
YES 1
ROLLOUT SWITCH CLOSED?
YESJ
BURNER OFF?
(CONTINUOUS FLAME CHECK)
YES _
NORMAL OPERATION:
LED #1 -- SLOW FLASH
LED #2 -- SLOW FLASH
YES _
THERMOSTAT CALLS FOR HEAT:
LED #1 -- FAST FLASH
LED #2 -- FAST FLASH
YES _l
PRIMARY AND SECONDARY LIMIT SWITCH.
CLOSED?
YES
IS COMBUSTION AIR
PRESSURE SWITCH OPEN?
YES
_
IS COMBUSTION AIR INDUCER
ENERGIZED?
YES
_
HAS COMBUSTION AIR PRESSURE
SWITCH CLOSED IN 2.5 MINUTES?
YES _
iN..___q2_, o
NO
NO
NO
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GAS VALVE OFR COMBUSTION AIR INDUCER OFF.
INDOOR BLOWER DELAY OFF.
LED #1 ON
LED #2 ON
(RESET CONTROL BY TURNING MAIN POWER OFF.)
POLARITY REVERSED,
LED #1 -- FAST FLASH
LED #2 -- SLOW FLASH
IMPROPER GROUND,
LED #1 -- ALTERNATING FAST FLASH
LED #2 -- ALTERNATING FAST FLASH
LEDs SIGNAL FAST ALTERNATING FLASH.
CONTROL WILL NOT RESPOND TO A CALL FOR
HEATING UNTIL VOLTAGE RISES ABOVE 95 VOLTS.
GAS VALVE OFF. COMBUSTION AIR INDUCER ON.
INDOOR BLOWER ON.
LED #1 -- ON. LED #2 -- SLOW FLASH,
SEQUENCE HOLDS UNTIL ROLLOUT SWITCH CLOSES
AND POWER IS RESET OR T'STAT IS INTERRUPTED
FOR MINIMUM OF 1 SECOND,
GAS VALVE OFR COMBUSTION AIR INDUCER ON.
INDOOR BLOWER ON HEATING SPEED,
LED #1 -- SLOW FLASH
LED #2 -- OFF
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COMBUSTION AIR INDUCER OFF.
INDOOR BLOWER ON
LED #1 SLOW FLASH RATE
LED #2 -- ON
GAS VALVE OFF:
COMBUSTION AIR INDUCER OFF.
INDOOR BLOWER OFF WITH DELAY,
LED #1 OFF
LED #2 SLOW FLASH
(Sequence holds until pressure switch
opens or thermostat resets control,)
PRESSURE SWITCH IS IN WATCHGUARD MODE.
GAS VALVE OFF: COMBUSTION AIR INDUCER OFF.
INDOOR BLOWER OFF WITH DELAY,
LED #1 -- OFF: LED #2 -- SLOW FLASH,
IS 5-MINUTE RESET PERIOD COMPLETE?
_ YES
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