I have a 2012 Puma fifth wheel and am experiencing problems with the furnace. When first turned on, the unit starts and heats as it should. It may even cycle 2 or 3 times properly but then starts to short cycle and /or blow cold air. Before the 2 or 3rd cycle starts the electonic board in the air conditioner clicks off and on several times. The most annoying part of the furnace cycle is when the flame is extinguished there is a small explosion, sometimes strong enough to rattle the door. I had it looked at by a tech this winter and he suggested the propane regulator was faulty as the propane heater and stove all "popped" when being turned off. I replaced the regulator but the problem has not been cured.