My 1972 22 foot Barth suburban propane furnace pilot flame will the not light by pilot procedure. Two small screws hold it position. If I engage the blower/run by the thermostat unit will light and run. Turn down the thermostat and the pilot stays lite. There is a small flame and an second slightly larger flame corresponding to the size of the 2 lines feeding. Could the lines be clogged? or should I look to replace the pilot assembly? (if i can find it) Thank you.

I don't get your problem sounds like it is working as it should??

Something is amiss.

For the pilot to stay lit, the thermocouple has be heated by the pilot. If the pilot goes out, the thermocouple cools and shuts off the gas, as a safety measure.

There should be only one flame.

How is the furnace lighting when you use the thermostat to turn on the blower? Or do you mean the pilot will stay lit when the blower runs?

If that's the case, the sail switch in the air handler keeps the main valve open.

I suspect that lighting the pilot with the blower on, then shutting down the blower, that the pilot will go out after a few minutes.

If that's the case, it points to a bad pilot thermocouple.

I'm not sure about the older units, but the newer ones do not have a pilot. They have an electric spark lighter. If you have a pilot and a thermocouple I would check the thermocouple, it may be stubborn when cold and on its' way out.

My newer heater has no pilot but the gas valve is leaking when it is supposed to be off. I can smell gas even when it is off. If it leaks enough, the gas would support a flame and mimic a pilot. In any case there should not be two flames.



Here is a picture of my setup. If you have a pilot and thermocouple it woud be mounted where my ignitor wire goes into the burner.

If the valve is leaking it will be burning near the valve.

My 1982 Suburban has a spark igniter, and the normal sail switch to open the gas valve, sounds like this one is real old school with a pilot and thermal couple. I am not sure why there is a second flame unless there is another hole in the line to the pilot area, or if there really are two flames, the thermocouple may just split the flame, but if when the thermostat calls for heat and it goes like it should what's the problem, of course, I assume it does shut off when the thermostat is satisfied. I also assume the pilot is lighted by hand and runs until the gas is exhausted or shut off.

So if it does have an electric flame starter , then if a smaller flame is present after the thermostat is satisfied, you have a leaking gas valve and should replace it before using or even turning the gas on. Unlike a water heater the furnace and flame totally is inside the coach.. Danger- Will Robinson-Danger!!!

One more thought, with a thermocouple unit if the primary valve is leaking, there would be two flames, the actual pilot and the main flame from the leaking valve. Either way don't use it! Propane is heavier than air so it will fill the lowest level of the coach, shut the gas off at the source.

quote:

Unlike a water heater the furnace and flame totally is inside the coach.. Danger- Will Robinson-Danger!!!

My water heater had a pilot burning. Steve VW told me that was a leaking gas valve. I had that fixed right away. Sounds like you should have someone that knows check it out.

Maybe fool around with adjusting the Air Shutter.

This adjustment has a huge influence in the size and type of flame.

-OR-

Sounds like the Gas Valve could be a problem.

Been at it so long I remember stuff like this. Had a '75 sportscoach with 2 Coleman furnaces that had pilot lights. No parts available as they had been pulled from the market, because of the danger. Anyway I could gary rig to make it usable, but if the flame went out the gas kept on coming. Fear caused me to end up replacing the furnace. I might be dumb but not stupid.

I ended up taking the pilot assembly out of the furnace. I used I thin diameter file to clear the ends. Replaced and it is working. Some black carbon residues were evident. I will try and find a replacement. Thank you for all the help...