Noticed that there is a weird carbon build up on the exhaust of my rear furnace. (see pics) The front looks fine. Anyone seen this before? Any idea what's causing it?
see ya
ken
Ken, This black stuff is a sure sign that combustion is not taking place properly. Several reasons, First is probably obstruction in burner, mud daubers, trash etc. Second is fuel air ration, burner burnt out, air restriction etc.
Remove the burner assembly and inspect the burner. Clean out the burner area.
Be aware that parts for these are almost nonexistent. You can get a burner by ordering a BURNER/IGNITER KIT and using only the burner.
Gary B
About 6 mouths ago I had Oregon Motorcoach look at my furnace. They said it was just dirty and blew it out and cleaned the screen. Unfortunately the carbon came right back. While at FOT I asked them to check it out and they found the flue had deteriorated. Got a scare when they said Atwood doesn't make them anymore. Might need a new furnace. Fortunately they did find there is a company still making them. Should have one on Tuesday. Alton said the black carbon is a clue that it's the flue.
see ya
ken