HEATING SEQUENCE OF OPERATION WITH
NORMAL HEATING MODE
IS THE S10 (S99) HIGH LIMIT CLOSED?
YES
IS W1 DEMAND OF
THERMOSTAT SATISFIED?
YES
A3 (A12) LED OFF
GAS VALVE CLOSES AFTER APRROXIMATELY 3 SEC. AND THEN
B6 (B15) COMBUSTION
AIR BLOWER OFF.
B3 SYSTEM BLOWERS OFF
AFTER 150 SEC DELAY.
NO
ABNORMAL HEATING MODE
DETERMINE WHY
RELAYS MAINTAIN BLOWER OPERATION.
NOTE − IF ECONOMIZER INSTALLED, ECONOMIZER OPERATES WHEN BLOWER POWERED.
LED CODES
1 − ON NORMAL OPERATION WITH THERMOSTAT CALLING FOR HEAT. 2 − 0.5 SEC ON AND 2.5 SECS OFF IN IGNITION RETRY PERIOD.
3 − OFF NO POWER OR DETECTED FAULT.
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