Advice needed: Furnace works at dealership, but not at home/camping.

[COHR]

Took camper in for a couple small things, including a large item - the Suburban SF-20 furnace not heating (separate thread about trying to light three times, but no luck).

However, dealer says they have it working just fine and when I come to get it, we'll walk through so they can verify I'm doing the steps correctly, etc.

If it works fine at the dealership, and I can see no signs of them "setting it up to work" just for when I'm there, but I still have problems at home or while camping and I'm following the exact steps we use to get it to work while in their service bay, what then? I suppose I'll record on my phone what I'm doing and the result to show them I'm not crazy. I tried so many times, different temperatures, permutations, etc. But it just runs fine for them? I must be doing something wrong, even though it should be as simple as setting the temp higher than the internal camper temp to get the thermostat to trigger the furnace, assuming good propane flow and 12v power.

Anyone have a similar experience, and if so, how did you resolve it? Am I nuts?

Thank you!

[mlong]

Does this happen all the time for you or just when you replace the propane bottles and the propane lines do not have propane pressure. You may need to bleed air from the system for it to light properly. Otherwise it will not detect a flame after a few tries and then shut down. If it works at the dealer when they light it. Have them turn it off and disconnect the propane. Hook it back up and see how they suggest you purge the air from the lines then relight. If all goes well there you should have no problem unless there is a bad part that allows intermittent use/failure.

I had a similar furnace in my pop up. It turned out the the thermostat was bad.

[COHR]

Originally Posted by mlong

Does this happen all the time for you or just when you replace the propane bottles and the propane lines do not have propane pressure. You may need to bleed air from the system for it to light properly. Otherwise it will not detect a flame after a few tries and then shut down. If it works at the dealer when they light it. Have them turn it off and disconnect the propane. Hook it back up and see how they suggest you purge the air from the lines then relight. If all goes well there you should have no problem unless there is a bad part that allows intermittent use/failure.

I had a similar furnace in my pop up. It turned out the the thermostat was bad.

Thanks. Yes, I'll try those steps with them. When I was attempting, I would light the stove to help 'prime' the main lines. I also tried the furnace several times, and could smell propane from the exterior exhaust vents. So, I'm nearly certain the propane line to the furnace was okay.

On your thermostat issue, was it triggering the operation of the furnace each time? Every time I try, it turns the furnace on, so I've been assuming the issue is beyond the thermostat. Could that be an incorrect assumption?

[mlong]

On mine, the thermostat would not even turn the furnace on. I don't think that would be your issue. I seems as though the ignitor is not working correctly. It could be a relay or something else.

[COHR]

Originally Posted by mlong

On mine, the thermostat would not even turn the furnace on. I don't think that would be your issue. I seems as though the ignitor is not working correctly. It could be a relay or something else.

Thanks. I'm thinking it's a propane flow issue with the auto-selector tee at the tanks, or maybe an igniter adjustment issue. Something subtle, that maybe knocks in/out of alignment to/from the service center or maybe something slightly wrong that's extremely altitude-sensitive (from 5300 ft to 9000 ft).

But, if I'm really super lucky, I'm just a bonehead and I'm doing one little thing wrong and I just need to have a kick in the pants to learn the right way. Those, while more embarrassing, are usually the most relieving in the end.

[mlong]

I'd rather be embarrassed by something I missed than having a broken item that costs hundreds to repair. Good luck. I hope you get it resolved