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Operating information
(continued)
OPERATION
DISPLAY
1. Upon a call for heat, the control turns on the appropriate pumps.
The flow switch and/or LWCO must close.
2. Once the LWCO has closed, the auxiliary limit switch must
close.
3. The control starts the pre-purge cycle by initiating the blower.
4. The control starts the trial for ignition by firing the spark
electrode and opening the gas valve.
5. If flame is not detected after the sparking ends, the control will
perform a postpurge, then start another prepurge cycle and try
to light the burner again. The control will perform a total of 4
attempts before locking out.
Installation & Service Manual
F I R E T U B E C O M B I
™