Problem with lp furnace

[MikeD3534]

I have a 2011 Alpine 3640RL. I don't know who makes the furnace, but i'm not sure it matters right now. When the thermostat initially calls for heat, the furnace blower starts, and I can hear the burner trying to start. It will shut down before the burner starts. I have to power the thermostat off and back on several times before the furnace will start and behave normally. I'm leaning toward thermocouple or LP solenoid? Thanks for any help.

[66joej]

Had that problem with our previous TT and it turned out that I was opening the propane tank too quickly and it shut off the flow from I believe the flow contol valve. Opened it slower and no more problem. Just a suggestion.

[chuckster57]

It sounds more like a bad control board. RV furnaces don't have a thermocoupler per say. Gas valve is controlled by board after 12V goes through a high limit switch and a sail switch.

When you call for heat at the thermostat the furnace fan starts. 12V is then sent through a ceramic sensor that will stop flow of electricity if the temp in the furnace is too high. Then the voltage has to pass through a sail switch. The sail switch is a long metal tab that sits in the path of the fan and when it's spinning fast enough to produce enough flow it will cause the tab to push the contacts together.
At that point the signal is back to the board and it will then open the gas valve and spark. Once a flame is sensed at the sparker the igniter stops.

Shutting everything off "resets" the board. I'm not saying that IS your problem but most likely is and further testing would confirm.

[sourdough]

It sounds like a problem I had when I first bought my trailer and they had to replace the control board. My solution at the time was the same as yours; shut off the thermostat to have the board reset. I initially pulled the cover outside and physically removed the power wire from the controller to make it work but later found out that shutting off the thermostat would do the same thing.....very irritating.

Whoops! Looks like Chuckster and I posted the same thing at the same time!!

[66joej]

I have a 2011 Alpine 3640RL. I don't know who makes the furnace, but i'm not sure it matters right now. When the thermostat initially calls for heat, the furnace blower starts, and I can hear the burner trying to start. It will shut down before the burner starts. I have to power the thermostat off and back on several times before the furnace will start and behave normally. I'm leaning toward thermocouple or LP solenoid? Thanks for any help.

Also somewhere on this site the problem turned out to be low voltage from undercharged batteries. Didn't say if you were on shore power or not.
Problem is more likely what the other theories are.