Montana furnace or thermostat not working well

[OregonTroy]

Have new Montana 3820fk with Atwood furnace and dometic thermostat. When I turn on furnace, i set fan to auto and then set temp. Blower turns on then furnace. Works great but once it turns off, it won't start again. The blower turns back on and I can hear the furnace trying to fire up but it doesn't. I have to completely turn off, wait a bit, and then turn back on to get working again.

Any ideas? What am I doing wrong?

[2Savages]

I noticed a similar thing for Air Conditioning on our 3820FK this last September during 90 plus degree days. I figured it was something to do with the technology. I would turn it off to reset and then turn it back on for AC. The heater worked fine for us, but was only on to warm the trailer up.

[Alpine]

Originally Posted by OregonTroy

Have new Montana 3820fk with Atwood furnace and dometic thermostat. When I turn on furnace, i set fan to auto and then set temp. Blower turns on then furnace. Works great but once it turns off, it won't start again. The blower turns back on and I can hear the furnace trying to fire up but it doesn't. I have to completely turn off, wait a bit, and then turn back on to get working again.

Any ideas? What am I doing wrong?

I was hoping someone would have responded to your question as I am having the same issue! Did you find the "fix?"

[Tbos]

Chuckster57, JRTH, do you have advice for these folks?

[chuckster57]

Occasionally these kind of threads get discussed between myself and the other tech here. Our thoughts are control board.

[JRTJH]

I'm really at a loss as to what it "would be". A couple of guesses on what it "could be": I agree with chuckster, control board is the most likely problem. But, it also "could be" carbon from a bad connection on the ignitor circuit. If it were mine, I'd look first for "soot" on the "sparking end" of the ignitor. If it looks clean, I'd focus on a replacement control board. My recommendation would be "Dinosaur Electronics" not the OEM.

As for the thermostat. It's essentially an "off/on" type device, so if it worked once, it will work the next time. I wouldn't think it would be the problem.

All of this is "best guesses" so it may well be "almost anything".... If the trailer is in warranty, let the dealer "deal with it"... If it's "just out of warranty" remember the appliances have their own warranty, the furnace is, I believe 3 years, so any "authorized service center" for that brand could do the work.

[Barbell]

Had a similar problem last winter. By holding something over the exhaust port on furnace, I could get it to light. After a while tho had to replace the igniter and no more problems.

[Tammysue]

Originally Posted by JRTJH

I'm really at a loss as to what it "would be". A couple of guesses on what it "could be": I agree with chuckster, control board is the most likely problem. But, it also "could be" carbon from a bad connection on the ignitor circuit. If it were mine, I'd look first for "soot" on the "sparking end" of the ignitor. If it looks clean, I'd focus on a replacement control board. My recommendation would be "Dinosaur Electronics" not the OEM.

As for the thermostat. It's essentially an "off/on" type device, so if it worked once, it will work the next time. I wouldn't think it would be the problem.

All of this is "best guesses" so it may well be "almost anything".... If the trailer is in warranty, let the dealer "deal with it"... If it's "just out of warranty" remember the appliances have their own warranty, the furnace is, I believe 3 years, so any "authorized service center" for that brand could do the work.

What is and where is the control board on 2009 Mountaineer?

[JRTJH]

The control board for the furnace is INSIDE the furnace. Pull out the owner's packet that came with your trailer and inside that packet is the owner's manual for the furnace (you'll find many owner's manuals in the packet). Go to the last few pages in that owner's manual and you'll find an illustrated parts breakdown. It will show you how the furnace is assembled and where each of the components is located on the furnace.

As a note, if you're not a "handman type", and you're asking "Where is the furnace control board located?" and you don't have much experience taking things apart/putting them back together (without ending up with spare parts), then I'd urge you not to start with the furnace as your first project..... While it's not "extremely complicated" it is not as easy as changing a light bulb on your range hood. So, depending on your mechanical interests and capability, you may find that taking it to the dealership or finding a mobile RV technician might be the better option.

[Tammysue]

Thank you for the information. I am new to working on trailers. I hope I have no problem.