Heater wont stay lit

[EForbes]

Hi guys, having a little problem with my central heating in my 5er.

You can here it lite, has a strong flame, them the flame turns off, then back on in about 30 seconds, and it repeats this process about 5 times, then just continue to blow cold air. When i can here it light, i can feel the air begin to get warm, but it never stays lit, for more than 5 seconds. I cant see the flame, but you can here it, and it sounds strong, and the exhaust is hot while its going.

Doesnt matter where i set the t-stat, its the same result.



Thanks for any help

 

[AClayton]

What make and model furnace?If it lights and proves flame,even for a short time,it generally means the flame sensor is good. It could be the circuit board bad but also improper gas pressure. Confirm good battery voltage and that your LP tanks are are full and then give us the make and model # of your furnace. Different make furnaces have different symptoms and common failures... . the reason it is necessary for the #s. BTW,just because you have good voltage at the battery doesn't necessarily mean the voltage AT the furnace is adequate... . check voltage at furnace.



Alan

 

[AMink]

Yep, start with your LP tanks. They might have enough to fire, but not burn. That's the cheap place to start. Will your stove stay lit?

 

[Hoefler]

I would bet you have a wasp nest problem. Probably a partial blockage which would cause an overheat condition in the heat exchanger. It will shut down the flame until it cools and then reignite.

 

[JDecanter]

Mine was acting the same way. It was the little toggle switch on the wall. I have replaced it twice.

 

[WestTN]

Mine did this years ago. It was rust flakes in the combustion chamber. It was a heck of a job to get rid of them.

 

[B.G. Smith]

On the outside of the trailer where the cover for the heater intake is mounted there should be a screw or two you can remove and pull the little cover off. You will be able to look into the intake tube and the exhaust tube to determin if there is and obstruction in there. bgl

 

[EForbes]

mine is a dometic, i have blown out the exhaust, not much came out, and on the inside under fridge, i removed a sheet metal cover, and the heat tube was all sealed, and heat duct where connected to outer part of heater box. On the outside of camper, there is no panel to remove to get to burner. The gas line and igniter face the inside of camper, i cant see only hear the flame. ready for more help

Thanks guys, oh its a 2000 model year fleetwood 5er

 

[RVTRKN]

More than likely your flame is proved through "Flame Rectification", which means the flame will allow a small measurable amount of current (micro amps) to flow through, and the sensor rod in the flame is the receiver and the Control Board reads it. Almost always the sensor is just corroded and it just needs cleaning, even though it may look OK there can be a problem. The sensor rod is easy to remove and clean it with a Scotch Brite pad and retest. The rod is an 1/8" rod that sits in the flame, before the flame enters the heat exchanger. You can send me a PM if you like and I will help you trouble shoot it.

 

[JMetzger]

I agree with RVTRKN. I had this very same thing happen on my house furnace, never the RV yet. I cleaned mine with steel wool & it worked fine. I clean it every fall before heating season. I should do the same to the RV but do not use the furnace that often.

 

[EForbes]

Thanks RVTRKN i will pm you when rdy to take a look at again, i put in storage sunday after trip, i will go get this weekend. Its a 2000 wilderness 30ft bunkhouse