Lennox G32V Series Service Literature page 59

NORMAL HEATING MODE
PROVE SWITCH CLOSED?
YES
TWO−STAGE MODE
CALL FOR 1st STAGE HEAT
CALL FOR 2nd STAGE
HEAT (HIGH HEAT)
FROM THERMOSTAT
INDOOR BLOWER SWITCHES TO HEATING SPEED.
CFM" LED−DS4 BLINKS ONCE FOR EVERY 100 CFM.
COMBUSTION AIR INDUCER SWITCHES TO
HIGH SPEED?
HIGH HEAT PROVE SWITCH CLOSED?
HIGH HEAT GAS VALVE OPEN? (8 SEC. DELAY)
TWO−STAGE MODE
CALL FOR 1st STAGE HEAT
CONTROL CHECKS: FLAME PRESENCE, CLOSED
PRIMARY LIMIT, CLOSED PROVE SWITCHES,
CONTINUOUSLY CLOSED ROLLOUT SWITCH (during
SEE PREVIOUS SEQUENCES FOR FAILURE MODES.
DEMAND FOR HEAT SATISFIED.
GAS VALVE DE−ENERGIZED.
COMBUSTION AIR INDUCER POST−PURGE 5
SECONDS. HTG ACC. TERM. DE−ENERGIZED
SELECTED TIME OFF DELAY.
HEATING SEQUENCE CONTINUED
YES
W2 TIMED MODE
SINGLE STAGE T'STAT
2nd STAGE ON DELAY
ON CONTROL BOARD
COMPLETE
(8, 12 OR 15 MIN.)
YES
YES
W2 TIMED MODE
SINGLE STAGE T'STAT
heating cycle).
THERMOSTAT OPENS.
INDOOR BLOWER
ABNORMAL HEATING MODE
NO
GAS VALVE DE−ENERGIZED.
INDOOR BLOWER DE−ENERGIZED.
COMBUSTION AIR INDUCER ON FOR 2.5 MINUTES.
PROVE SWITCH WATCHGUARD
¦ 2.5
MINUTES
NO
SINGLE−STAGE MODE
HIGH HEAT ONLY
LED #1
SLOW FLASH
ON SLOW FLASH
SLOW FLASH
SLOW FLASH
OFF
SLOW FLASH SLOW FLASH
FAST FLASH FAST FLASH
FAST FLASH SLOW FLASH
SLOW FLASH FAST FLASH
ON
ALTERNATING SLOW FLASH
ALTERNATING FAST FLASH
Page 59
PREPURGE
(See top of previous page.)
PROVE SWITCH
CLOSED?
COMBUSTION AIR INDUCER
DE−ENERGIZED.
5−MINUTE DELAY
COMBUSTION AIR
INDUCER ON.
DIAGNOSTIC CODES
LED #2 DESCRIPTION
Primary or secondary limit open
ON
Rollout switch open
OFF
Flame sensed without gas valve energized
PROVE switch open
Power on
Heating demand
Polarity reversed
Low flame signal
ON Circuit board failure
Watchguard −− burners failed to ignite
Watchguard −− low voltage, below 75V or
improper main ground.