Atwood Furnace Repair

I have been having problems for some time with the Atwood model 8516 furnace in my ATC Panther. It would light, run for one or two cycles and then not relight. I thought I would pass this repair information on to anyone who might be having a similar problem.

I finally traced the problem to the air flow switch (sail switch)located in the fan shroud. It would stick in the open position after the fan shut down and not allow the furnace to relight. The fix was to remove the front half of the fan shroud and replace the switch. Not too big of a job although it requires removing the igniter board to allow the shroud to be pulled out of the furnace.
On inspection I could see a mark on the fan shroud where the switch lever was rubbing and bent the switch lever slightly so there was more clearance.
So far so good, seems to work ok, it will remain to be seen if it works in very cold weather.
Dsrtrat

dsrtrat, thanks for the tip. My old Atwood did this once to me, failed to relight. I've not bothered to look into it because it did not happen again. Appreciate your post as now I'll have a likely suspect!

We seem to have a similar issue with our furnace in that it needs to be reset. thus far it's only happened at night, wake up to hear a slight buzzing sound coming from the furnace and a flashing red light. Need to pull off the front cover and hit the reset button. We'll go days with the thermo set at the same temp and no problems then we'll have the problem. No idea what the issue is.

dsrtrat....is this what you're was doing?

Sorry for the late reply. Yes, what you describe was the same problem I had. The switch is pretty easy to change and a low cost item. $10 at the local RV place or cheaper on line. I would change it out and see if it solves the problem. The switch location is behind the front fan shroud and its 4 screws to take the shroud off after you pull the igniter board.

I think what was happening with mine was the switch lever may have been hitting the fan shroud and not closing at the end of the cycle. If you listen carefully you can hear a very quiet click as the fan slows down after shut off. This is the switch returning to its off position.

The micro switch is exposed to a lot of dust in its location inside the shroud and I think mine was possibly full of dust. I haven't had the chance to try it out in really cold weather yet and will report back if I am still experiencing the problem after a cold camping trip.

The other thought I had about cold weather furnace problems is drop in tank fuel pressure due to the cold or regulator icing.






We seem to have a similar issue with our furnace in that it needs to be reset. thus far it's only happened at night, wake up to hear a slight buzzing sound coming from the furnace and a flashing red light. Need to pull off the front cover and hit the reset button. We'll go days with the thermo set at the same temp and no problems then we'll have the problem. No idea what the issue is.

dsrtrat....is this what you're was doing?

Thanks dsrtrat, I'll give that a try the next time I have access to the camper and report back. Do you have the switch part number or a web-link? I might just purchase it and throw it in...for $10 seems worth trying.

I know this is an old thread but I've been trying to figure out how to light, etc., etc., my atwood 8516. I have all the access panels off and I see an on/off switch under one of them. I don't have a thermostat or anything else and can't find a manual which describes how to turn it on, etc. The schematics show an optional thermostat, etc. but nothing on how to run the thing or set a temp, etc. Any help or directions you can share?