Those Atwood furnaces were pretty darn reliable.
Usually, not always, but usually you can tinker with it and get it running again.
Spend a few minutes, it might be worth your time since Winter is coming.
Easy things to try ...
STEP 1:
Plug your camper in to shore power (ex: your garage) if you can, or make sure your aux. camper battery is fully charged for this testing below, or if your camper is properly wired up to your truck, start your truck up and have your truck running when you are doing the tests below. This will ensure you have a good amount of power being supplied to the camper.
STEP 2:
Make sure you have a full tank of propane, and that the propane tank valve is "open".
NEXT STEPS:
3. remove the thermostat cover on the front of the kitchen cabinets. there should be 2 blue wires in there, one wire attached to a screw, and another wire attached to a different screw. Make a jumper wire (bend a paper clip) or unscrew the two wires and touch them together. This should start the furnace fan, and shortly after the furnace will ignite if everything is working properly. If the furnace starts and works after you touch those 2 wires together, you probably just have a bad thermostst. Just get a new one from us, an RV shop, or most hardware stroes will have something similar.
If that doesn't work, then try ...
4. remove the furnace cover on the outside of the camper (4 small screws).
4. remove the furnace vent covers off the inside of the camper cabinets where the furnace (probably 4 small screws for each vent cover).
5. blow both areas out with compressed air.
6. look inside with a flashlight to see if anything looks out of wack. Loose wires, broken fan blade, etc.
7. find the small toggle / rocker switch in there. this is usually visable from the outside of the camper. reset it (turn it one direction, wait a second, and then flip it back to the original setting).
Try and set the thermostat again and see if the furnace fires up as it should.
If that doesn't work, poke around inside a bit more and fiddle with the wires and look for anything out of the norm.
If all of the above fails, you might need to take it in to an authorized Atwood RV service center.
But hopefully something above will work and save you a few bucks, time, and hassle of taking it to a service center.
Happy Camping !
.