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Propane furnace "POOFS" several times when starting heat cycle

Propane builds up in the heat chamber and when igniter turns on it "poofs" or has a mini gas explosion several times before the burners settle down and continue to burn correctly. Furnace does work correctly after several poofs. Burners were removed and cleaned and are in good shape, ignitor rod can be seen turning red, Could this be a regulator problem?
thanks, cliff

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I'm not sure how you are going to solve this, as propane's relative gas density is 1.55 times that of air, causing the gas to "pool" up in the bottom of the ignition chamber... After you are hearing the "poofs", the chamber is probably warmed up and the convection of the column of air rising then prevents the pooling of the gas towards the bottom. Hence the poofing goes away. Is there a pre-warmer or something that you are missing?...

Posted on Mar 12, 2009

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Sounds as the regulator is not operating correctly (possibly the control board)

Posted on Mar 12, 2009


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