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CONTINUOUS LOW SPEED FAN SEQUENCE OF OPERATION
LED: SLOW FLASH RATE REMAINS
UNCHANGED THROUGHOUT SEQUENCE.
MANUAL FAN SELECTION MADE AT THERMOSTAT.
CONTROL (G) ENERGIZES SYSTEM FAN AT ACB
LOW SPEED. ACC. TERMINAL IS ENERGIZED.
THERMOSTAT CALLS FOR HEAT (W).
THERMOSTAT CALLS FOR COOLING.
BOARD NO. 63K8901
SYSTEM FAN DE-ENERGIZED. SYSTEM FAN
ENERGIZES ON ACB HEAT SPEED AFTER
NORMAL DELAY.
THERMOSTAT OPENS. COMBUSTION AIR
AND HTG ACC TERMINAL DE-ENERGIZE.
SYSTEM FAN SWITCHED TO ACB COOL
SPEED. ACC. TERM. REMAINS ON.
THERMOSTAT OPENS.
BOARD 63K89: SYSTEM FAN OFF. ACC. TERM.
OFF. (AFTER OFF DELAY COMPLETED).
MANUAL FAN SELECTION MADE AT THERMOSTAT.
CONTROL (G) ENERGIZES SYSTEM FAN AT ACB
LOW SPEED. ACC. TERM. ENERGIZED.
NO
YES
YES
NO
HTG ACC. TERM. ENERGIZES
WITH COMB. AIR BLOWER.
BOARD NO. 24L85, 56L83, 97L48
SYSTEM FAN SWITCHES TO ACB HEAT SPEED
AFTER NORMAL DELAY (fan remains energized)
BOARDS 24L85, 56L83 AND 97L48:
SYSTEM FAN SWITCHES TO
LOW SPEED AFTER NORMAL DELAY.
(fan remains energized)