Lennox G50UH Series

Page 39
G50UH Series
SureLight
®
Troubleshooting: Continuous Fan Sequence of Operation
SURELIGHT
®
CONTROL
CONTINUOUS FAN SEQUENCE OF OPERATION
LED: SLOW FLASH RATE REMAINS
UNCHANGED THROUGHOUT SEQUENCE.
MANUAL FAN SELECTION MADE AT THERMOSTAT.
CONTROL (G) ENERGIZES INDOOR BLOWER AT
FAN SPEED. EAC TERM. IS ENERGIZED.
THERMOSTAT CALLS FOR HEAT (W).
THERMOSTAT CALLS FOR COOLING.
THERMOSTAT OPENS. COMBUSTION AIR INDUCER
AND HUM TERMINAL ARE DE−ENERGIZED.
INDOOR BLOWER SWITCHES TO COOL SPEED.
THERMOSTAT OPENS.
INDOOR BLOWER SWITCHES TO FAN
SPEED. EAC TERM. REMAINS ENERGIZED.
NO
YES
YES
NO
HUM TERM. ENERGIZES
WITH COMB. AIR INDUCER.
INDOOR BLOWER SWITCHES TO HEAT SPEED
AFTER NORMAL DELAY.
INDOOR BLOWER SELECTED TIME OFF DELAY BEGINS.
AFTER DELAY HEAT SPEED DE−ENERGIZED.
(blower remains energized during continuous fan mode).