Atwood Furnace with Flames in Exhaust

[rv46]

I am posting this on behalf of a friend.

He has a Atwood furnace which appears to work (i.e. blows hot air out the vent). However, he notice that there are some flames coming out of the exhaust. Suggestions?

Thanks.

[mchero]

Furnnace needs a good cleaning

[rv46]

Thanks for the suggestions. I have passed them on.

[3oaks]

My first guess would be inadequate combustion due to air/fuel mix ratio. Often caused by cob-webs or a dead bug or two in the orifice tubing. Usually only takes a little compress air to clear. What needs cleaning is exposed just by taking off the outside vent cover to the furnace.

[darsben]

rv46 wrote:
Correction, not flames but dark black smoke is coming out. (Sorry for the confusion.)

Since we are long distance troubleshooting a second hand problem. The thick black smoke makes me feel the combustion chamber is plugged up and proper fuel/air ratio not being achieved. He will need to pull the unit and clean it out.

[rv46]

Correction, not flames but dark black smoke is coming out. (Sorry for the confusion.)

[rv46]

His RV is a 1996. Unfortunately the "hunting" RV is in Missouri and he is in Alabama. He will be heading up there shortly to fix the issue and was looking for suggestions before he goes. Thanks.

[beemerphile1]

dougrainer wrote:
Do not use it until it has been checked out by a qualified Technician. Doug

My thought also, shut it down immediately and turn off LPG. Do not use again until serviced by a qualified technician.

[Old-Biscuit]

Sooted up --- rusty causing 'sparks'

Need to clean combustion/exhaust chamber

[2oldman]

I'd love to see a pic of that!

[rv46]

I will pass these questions along. Thanks.

[dougrainer]

Do not use it until it has been checked out by a qualified Technician. Doug

[j-d]

Another possibility is debris (usually a wasp or mud dauber nest) in the tubes leading to/from the furnace.

No harm in checking, but heed darsben's warning, if the burner is rusted through, exhaust from it can enter the interior of the RV.

[darsben]

Without enough info the first thing to check is propane pressure and burner orifices. Burner could be rusted out.

Really nee to know how old a unit, any other propane related problems. Was fridge checked for propane operation and does the stove have a proper flame?