Atwood Furnace help

[chuckster57]

Originally Posted by LHaven

I wouldn't feel safe assuming that a battery tender wasn't acting as a vampire load on your battery when it wasn't plugged in. I'd throw an ammeter in that loop while everything else is unpowered, just to reassure yourself.

I have to agree. An amp gauge would tell the real story.

[kcamp99186]

Thanks to you both! I will check and post my findings.

[Aireman]

I know this sounds caveman, but when I had a mobile tech come check mine for the “ fan runs and turns off without ignition “ problem , he pounded on the top of the unit in the fan just starting cycle. It kicked on and he knew to change out the sail switch. He used the Atwood warranty and charged me just $45 bucks.

[66joej]

Yep that's how the Tech did the troubleshooting on mine. Same problem same fix.

[plgamble]

I am having the same problems with my DFMD35-121 furnace, in a 2018 Outback 210 urs. Fan comes on, no ignition. I have learned the circuit boards are suspect, and fail often. If you go in for warranty work, you will get the same OEM board. Insist on the Dinosaur brand, or call them at 541-994 4344, and provide your model number for the correct board. I don't have an outside door, so I am ordering the sail switch and limit switch from Amazon, and the board from Dinosaur, just in case. But given the reputation of the OEM boards, and the difficulty of furnace removal, I'm putting the board in no matter what, and will carry the OEM as a spare.

While I'm waiting on parts, does anyone with same or similar model know about how much slack is in the wires, and how to rig up temporary propane supply for bench testing?

Thanks for any input!

Phil

[66joej]

Originally Posted by plgamble

While I'm waiting on parts, does anyone with same or similar model know about how much slack is in the wires, and how to rig up temporary propane supply for bench testing?

Thanks for any input!

Phil

No slack in the wiring harness. Have to be cut and use butt connectors to reattach the harness.

[chuckster57]

Originally Posted by 66joej

No slack in the wiring harness. Have to be cut and use butt connectors to reattach the harness.

That’s about typical for any furnace in any trailer.

[Roscommon48]

just to many variables....get to a repair shop. it could just be your LP reg. or low tanks too.

[plgamble]

Thanks for the pointer on the regulator. During our last trip, I was getting squirrelly propane readings on the regulator gauge, even when the tanks felt full. I have ordered a mechanical propane scale, and, a screw on adapter gauge.

The stove works fine, and the fridge ran on propane ok while boondocking and travelling, could there be a gas pressure problem with the regulator that affects the furnace only? Thanks to all for your help!

Phil

[sourdough]

When this last regulator failed (2-3 months ago) it did affect the furnace. The stove would burn but if I turned on all 3 burners and let them go they were at a reduced flame from normal. As it got worse they would come on and eventually die. I figured the furnace tried to pull more LP than the regulator would allow. New reg and all was good.

[kcamp99186]

I have checked my sail switch, closes every time. Actually changed it last year when the issue began, but have kept the old one as backup because it was good. Never considered the regulator. I've experienced propane issues before and am now wondering if that may be part of the problem. I'll try the "burner test". I'm awaiting a new board and my furnace currently resides in my garage until it comes. Also adding another heat vent thru the wall into the bathroom. There is an AC vent there (brrrr) but no heat. We've always left the door ajar in cold weather. With the furnace out I can easily add this vent.

[jsmith948]

There have been several posts about Atwood furnaces failing to light.
A new control board fixed ours.
I recommend a board from Dinosaur Electronics.

[kcamp99186]

New Dinosaur board installed, still not working. After more troubleshooting, it seems I have a bad overtemp switch. Replaced the switch and back to normal (hopefully). Still need to run the furnace for an extended time to be sure. How did that switch work part of the time?! RV's can drive me nuts. lol I did check the parasitic load of my battery tender and found it to be less than 10mA. Not sure how accurate my Fluke meter is, so someday I'll check it again with a clamp on unit. If the camper is parked, the tender is powered. Only time it is not is when we're actually camping, so I'm not overly concerned. Thanks to you all. This group is the best!

[atkinsb3]

Originally Posted by sourdough

When this last regulator failed (2-3 months ago) it did affect the furnace. The stove would burn but if I turned on all 3 burners and let them go they were at a reduced flame from normal. As it got worse they would come on and eventually die. I figured the furnace tried to pull more LP than the regulator would allow. New reg and all was good.

My furnace has been doing the same. If I lit a stove burner and then tried the furnace again it would lite. Or if I turned the tanks off and cleared the gas lines the furnace would lite after I turned the tanks back on. I haven't tried lighting all the stove burners to see if they eventually drop or die but plan to do that.

I was thinking regulator but got to reading and was leaning toward the sail switch. Given the option of pulling the furnace out to check the sail switch or trying a new regulator, I think I'll run the burner test and hope it leans toward the regulator.