Instruction Manual

Page 12
Abnormal Operation (cont’d)
4. Trial for Ignition Fault:
A) Pressure Switch / Blower Temperature Switch Opens During Trial: The gas
control stops the trial for ignition. The gas control monitors the pressure switch
until it closes. If the pressure switch closes within 30 seconds, the gas control
will continue with the trial for ignition starting at blower pre-purge.
B) Flame Not Sensed: The gas control energizes the spark igniter attempting to
light the pilot and prove flame. If flame is not sensed within 90 seconds, the
spark igniter turns off, the pilot valve is closed, and the gas control runs the
blower through postpurge. The gas control LED flashes 6 times then 1 time with
3 second pause. The control waits 5 minutes before repeating the ignition
sequence.
5. Flame Sensing Fault:
A) Flame Lost During Run: The gas control turns off pilot and main valves and runs
the blower for 15 seconds (inter-purge). The gas control increments the recycle
count, if the recycle count has not reached its limit (4), another trial for ignition
begins. If the recycle count has been reached, the gas control LED flashes 6 times
then 3 times with a 3 second pause. The gas control waits 5 minutes before
repeating the ignition sequence.
B) Flame Sensed Out of Sequence: The gas control only looks for pilot flame when
the blower is running. If flame is present when the pilot valve is not open, the gas
control continues to wait for flame loss and flashes 5 times with 3 second pause.
This continues until flame is lost. Once the flame signal is lost, the control flashes 6
times then 4 times with a 3 second pause. The control waits 5 minutes before
repeating the ignition sequence.
Sequence of Operation
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