Problems with hydro flame 8500IV

[Colby4bush]

My Atwood furnace on my 2001 sunnybrooke is only blowing Cold air! I’m guessing maybe the sail switch or circuit board needs replaced! Does anyone have a tutorial on how to check or information they can help me with? I’d like to learn how to do this on my own instead of taking it into a repair shop! I have 12+ ears as a mechanic but this is all kind of new to me!

Thanks in advance

[trvler]

Hi - I have a 2007 31' Classic with a Atwood 8535-IV furnace. Last month it stopped working properly - would run for about two minutes blowing cold air, and then quit. The circuit board indicated a no.1 fault (Air flow/Limit Fault). I dismantled the furnace blower (from the outside, without removing the furnace) and discovered that the problem was the sail switch was improperly placed, and rubbing against the outside housing (sticking, in other words). I fixed that, and all is good now.
Not sure from your description whether this could be your problem. If your fan runs continously without heat, I would doubt it is either the sail switch or the limit switch, both of which would tell the circuit board to quit after a couple of minutes of trying.

Paul