Atwood Furnace starts then stops - sounds water logged

[ependydad]

We were gone all day today with the HVAC system off. We went to start the furnace; the fan would run for a bit and then would stop until we cycled the thermostat off and back on.

I first checked propane out at the change over valve and it’s showing green. I then checked the stove and was able to run all 3 burners for a bit.

I went outside to see if I could see or hear anything funky. It’s late so I didn’t take anything apart and can’t see anything. But I could hear it and it literally sounds water logged.

Here's a video of the noise:
http://www.youtube.com/watch?v=3X4_RXldhA0

I can honestly say I’ve never intentionally listened to my furnace ignite before, so maybe this is normal.

The outside temperature is about 60F. Inside temp says 67F and I’ve set it to 75F. It has rained for almost 24 hours straight- very hard at times. We HAVE used the furnace successfully before for hours at a time.

The 12v fuse seems OK. The LED light does not indicate a problem (though I know they’re unreliable). I pulled the fuse and the furnace doesn’t even attempt to start.

The furnace IS under the edge of a slide out’s slide topper rail that dumps runoff water directly onto it.

Any thoughts?

[ependydad]

BFL13 wrote:
Thanks to Doug for being on the Forum and still helping guys out. (He has said he gets fed up sometimes with repeating the same things, so extra credit for sticking around!)

Doug has set me straight a few times, and helped me with some trouble-shooting on my RVs here too, so I just wanted to throw in that I hope he keeps helping us.

Agreed. Thanks, Doug. (From another Doug.)

[ependydad]

dougrainer wrote:
Good Video. Bad news. Atwood will probably not be responsible for this problem as it is a bad install by the OEM. Yes, the design and run off of the slide cover has caused your water intrusion. The removable door needs to be installed better with a better gasket. DO NOT use silicone to seal the removable door. Your real problem is the vertical mount. It is OK to install vertical, but you must take special care tom prevent water intrusion. Your interior where all the water is, is causing the circuit board to not function. If you dried out the area and the circuit board the furnace would probably run correctly. The furnace will NOT run if you leave the chrome exhaust pipe OFF. You can just insert it into the exhaust metal pipe to run the furnace once it is dried. Without the metal exhaust pipe installed the intake impellor will just draw exhaust gas back into the chamber and snuff out the flame. If it was my unit or my customers unit, I would make and install a drip cap on top the furnace mount to make sure the water could not flow down the side of the furnace from the slide cover. Doug

That's the weird thing- in person, it looks like the circuit board itself is dry. Everything that is wet is below that separation. Everything above it seems to be dry. ...... I think.

My concern is that I don't know who installed the slide topper/awning rail since the unit did NOT come with slide toppers from the factory. I had the dealer (who is now 1000 miles away) install them. If it was the dealer, then I'm basically screwed without a fight to get reimbursed for whatever work has to be done to correct this issue. I'm asking some friends with a Spartan 1245 of the same year as mine.

Any thoughts on how to dry this thing out?

[BFL13]

Thanks to Doug for being on the Forum and still helping guys out. (He has said he gets fed up sometimes with repeating the same things, so extra credit for sticking around!)

Doug has set me straight a few times, and helped me with some trouble-shooting on my RVs here too, so I just wanted to throw in that I hope he keeps helping us.

[dougrainer]

Good Video. Bad news. Atwood will probably not be responsible for this problem as it is a bad install by the OEM. Yes, the design and run off of the slide cover has caused your water intrusion. The removable door needs to be installed better with a better gasket. DO NOT use silicone to seal the removable door. Your real problem is the vertical mount. It is OK to install vertical, but you must take special care tom prevent water intrusion. Your interior where all the water is, is causing the circuit board to not function. If you dried out the area and the circuit board the furnace would probably run correctly. The furnace will NOT run if you leave the chrome exhaust pipe OFF. You can just insert it into the exhaust metal pipe to run the furnace once it is dried. Without the metal exhaust pipe installed the intake impellor will just draw exhaust gas back into the chamber and snuff out the flame. If it was my unit or my customers unit, I would make and install a drip cap on top the furnace mount to make sure the water could not flow down the side of the furnace from the slide cover. Doug

[ependydad]

I opened it up. There’s definitely water inside there but I don’t have an obvious indicator of how it’s getting in.

I opened the basement’s rear wall and didn’t see signs of water down there nor on top of the furnace itself.

https://www.youtube.com/watch?v=vy8I4Pj4Y3w

[ependydad]

dougrainer wrote:
In 38 years of being a RV Tech, I have never heard such a noise from a furnace. The unit will have to be pulled to check it out. Water cannot get to the burner unless you shot water directly in with a water hose and even then it would take a minute or so for the water to get to the burner assbly. Rain water cannot get that far. Atwood has a 2 year warranty. Is yours still under the 2 years? Doug

“In 38 years never have I ever” seems like the story of my dang life! 🙂

Yes, I’m week 4 or 5 of ownership. I’ll get it checked out.

[dougrainer]

In 38 years of being a RV Tech, I have never heard such a noise from a furnace. The unit will have to be pulled to check it out. Water cannot get to the burner unless you shot water directly in with a water hose and even then it would take a minute or so for the water to get to the burner assbly. Rain water cannot get that far. Atwood has a 2 year warranty. Is yours still under the 2 years? Doug

[ependydad]

Artum Snowbird wrote:
I would think that you have a stuck "thing" in the furnace squirrel cage motor. It's stopping because there isn't enough flow to trigger the flow switch.

But, that is my opinion.

Would that make the warbling sound?

[Artum_Snowbird]

I would think that you have a stuck "thing" in the furnace squirrel cage motor. It's stopping because there isn't enough flow to trigger the flow switch.

But, that is my opinion.