Dometic RV furnace popping fuses

[KRS]

My folks' Forest River Wildcat 29BHS travel trailer has a dometic furnace under the fridge.

It's on shore power.

The furnace pops fuses as soon as the thermostat is turned on.

I pulled the interior access panel.

Then I removed a sheet metal panel from the furnace.

It revealed the burner tubes.

I used a very bright flashlight and I think I can see a squirrel cage fan back behind the burners. Threaded a broken fishing pole tip back there and tried to turn the cage. Couldn't get anything to budge with the very limited motion I had. Not even sure if that's the squirrel cage.

Looking for help / ideas.

Thank you,

KRS

 

[MTboatguy]

Re: Dometic RV furnace popping fuses

Sounds like the circulation motor has gone bad, you should be able to order one from any good RV dealer, you will need to get the model number off of it, and possibly the BTU rating so they can order the correct one, there are also several dealers that have internet stores, should not be hard to find, then you will have to take the furnace out and the case off of it to replace the motor. It is not uncommon for these to go bad due to the fact they normally don't get as much use as a home furnace.

One other thing to check is the control board, I have seen these blow fuses also.

 

[dvandsm64]

Re: Dometic RV furnace popping fuses

i'm just guessing ,but did u just put the battery in the camper. if so make sure the leads are hooked up rite. i think the furnace fan motor is fed from and the furnace lites from the battery.

 

[MTboatguy]

Re: Dometic RV furnace popping fuses

The power center normally has a resettable circuit breaker to prevent damage if the battery is hooked up backward and everything in the trailer would be dead.

 

[KRS]

Re: Dometic RV furnace popping fuses

Just looked through exterior vents (two chromed vents on side of trailer) with a very bright flashlight and I see mud dauber nests in both vents; and one nest appears to be attached to the squirrel cage fan.

Good Grief !!!

KRS

 

[MTboatguy]

Re: Dometic RV furnace popping fuses

Sounds about normal, mud daubers are drawn to propane, that was one of the things we always encountered when working on propane appliances, another thing that can cause the fuse to blow is the control board has gone bad. Last I checked the boards run around $125.00 depending on where you are in the country.

Do you happen to know the model number of this furnace? If so, I should be able to look it up in my manuals.

Just for future reference, Dometic makes screens to go over the intake and exhaust vents on the outside of the trailer that will prevent the mud daubers from getting in a making a nest, they sell for about $7.00 Cheap insurance to help prevent problems. You might even be able to find a off brand screen at Wal Mart.

 

[KRS]

Re: Dometic RV furnace popping fuses

It's a Suburban SF-30F.
Pulled it today.
Ruined the dual chrome exterior vent... can't seem to find one...?
Do I use the 'ribbon' style sealant to put the vent back on?

Okay, pulled the furnace.

Removed the screws that hold the black squirrel cage fan shroud on, slid the shroud as far as I could to the side. Broke up the stuff, scraped, blew it out, and cleaned some more.

I think I got it all.

Going to put it back together this weekend.

Need the chrome thing and some sealant(s).

Thank you all for your help,

KRS

 

[MTboatguy]

Re: Dometic RV furnace popping fuses

We used to use what we called "par tape" which was a flexible clay compound tape, that could be trimmed around the edges and then covered the top par with a bead of silicone sealer to keep water from penetrating.

If you have a battery and have it out, you should do a bench test before reinstalling to ensure everything is working correctly.

 

[KRS]

Re: Dometic RV furnace popping fuses

Tested, finished instal, replace exterior dual-vent, sealed that up.... good to go!

Thanks for the help,

KRS

 

[foodfisher]

Re: Dometic RV furnace popping fuses

So, was it the muddabber nest or other debris?

 

[KRS]

Re: Dometic RV furnace popping fuses

Mud dauber nest, attached to fan and fan housing; fan couldn't spin.

Ordered a mud dauber screen, it will be at the dealer on Wednesday.

 

[foodfisher]

Re: Dometic RV furnace popping fuses

Pesky little devils!Thanks.