Page 36 Part # MCOSM06 Rev 1 (11/03/08)
Fig 3 Sequence of OperationStart
Thermostat
call for heat
Prepurge
Trial for
ignition
Main valve
ame sensed?
Yes
No
Interpurge
Maximum
number of trials
attempted?
No Yes
Ignition lookout
(optinal LED
ashes)
No Control
with ignition
recycle?
Yes
Yes
Recycle delay
period
Flame present when
not expected
No Yes
Flame
present for
30 seconds?
Detected fault
Hard Lockout
(optional LED
turns o)
Run
Flameout?
Yes
Sixteenth
ameout?
No
No
Yes
Thermostat
callin for heat?
No
De-energize
control and valves
End