Limit switch trips on Atwood furnace
My 1993 Jayco Motorhome Atwood furnace fan runs for @ 12-15 sec then the furnace ignites, it runs for a sec or two, then the limit switch trips.
Forum Discussion
What makes you think it is the Limit Switch??
High TemLimit Switch would need more time for overheating
Flame igniting then shutting down is symptom of 'Flame Proving' failure
That happens with in just a 6=8 seconds
Flame generates an AC current that gets rectified into a DC Current that circuit board is looking for...no signal/circuit board shuts down DC to gas valve so raw fuel does not accumulate.
Flame sensing is via Spark Electrode/Ground Rod
Must be CLEAN cause signal is only a few milliamps
High TemLimit Switch would need more time for overheating
Flame igniting then shutting down is symptom of 'Flame Proving' failure
That happens with in just a 6=8 seconds
Flame generates an AC current that gets rectified into a DC Current that circuit board is looking for...no signal/circuit board shuts down DC to gas valve so raw fuel does not accumulate.
Flame sensing is via Spark Electrode/Ground Rod
Must be CLEAN cause signal is only a few milliamps
