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Ok guys.. there has to be a HVAC guy among us who might better understand my problem and can give some guidance. My RV Furnace is not cycling on properly. Basic issue is.. I can turn on the furnace at the thermostat, the furnace will run and get up to temp. Once the tem drops again, it will not cycle back on, BUT I can click the switch on the thermostat off and back on again and it runs fine until it reaches temp and turns off and then it wont cycle on again until I turn it off and back on. I've replaced the thermostat and issue continues. I took it in last winter and they told me that it runs just fine, however, I normally camp/hunt and 10,000 ft and obviously, the RV service center couldn't replicate altitude. The next think I am going to do is replace the LP regulator, I am not sure if this is the issue, but it cannot hurt. I've read about LP regulators having issues at altitude and if the furnace is not getting the correct amount of propane to it, the safety mechanisms set in and prevent it from turning back on.. I've also read about the 'sail switch' being the potential issue, but that doesn't make sense since it turns back on when manually turn it on over and over.. Any thoughts appreciated...
Same thing happened to mine and it was a bad connection in a wire that runs behind the refrigerator.
I would think Maybe the air flow swith is sticking after power is on and then off maybe resetting it , just and idea ,
Altitude sickness ? Lol
I’m about to replace a water heater. $415!
Does your unit keep a pilot lit once started or is an electric spark each time? I had a unit once that was electric start, then kept a pilot on until manually shut down. When that pilot got plugged it acted just like you're describing.
I had a problem like that and it was the thermostat itself. I put in a battery powered digital thermostat and all is now well.
Mine did the same thing, replaced the t-stat, no change. It ended up being the electric start circuit board. $85 on amazon
If you take the cover off your t stat , you will see a dial that can be adjusted for how long the heat cycle will run after reaching temp. Play with that to see if you can adjust the cycle to a shorter duration. if that doesn't work, I would agree that you have a bad t stat.
All you are doing by turning the thermostat off and then on again is resetting the system. Does your thermostat control your air conditioner as well? More than likely it does and as such I would start at your control to see if you are getting the signal to the thermostat after it reaches temp. The problem is not with your regulator if it will start initially and run to temp. You can check the sail switch with a meter to see if it is stuck open....it can happen, it is just not very common.
Backpack. No, my thermostat is for furnace only. I considered the sail switch, but my understanding is that it would stay in open position unless it was jostled, vibrated or alike to unstuck and it.. the return signal to the re-start makes sense. How would I test that?
I had trouble with my furnace years ago in my pop-up trailer. The temp sensor that is next to the pilot light would get soot/carbon coating. Clean that and it was good to go.
I'm sorry I miss typed on the sail switch. I meant to say you can check to see if it is stuck closed not open.....again, it can happen but is not very common.
The way to check the return signal is to see if you are getting power from the control to your thermostat when it is in the failed condition.
If you know the model number I can get you the exact sequence of operation, and it should be as easy as following the electricity.