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whisperwhillow 11-10-2015 07:05 AM

FR Toyhauler 377v furnace ?
Not sure what model furnace I have -- not sure where to find that yet, but it doesn't appear to be working properly.

It's pretty cold here in Colorado, and it was freezing in the RV last night -- and this morning! It just doesn't seem to be kicking on. I turned the heat off and back on and it came on and then went back off.

Hubby thought he would "kickstart" it by turning it to Fan mode and then to heat, but now it appears to be stuck in Fan mode, I think, because when I turn it to Furnace, cool air comes out both heater and a/c vents.

In either case, and as an added note, when it's gotten cold before and the heater doesn't kick on at night, something seems to happen around mid morning when it warms up a bit because it will typically kick on with warm air.

Any suggestions on what I could be looking at here as a problem?

TIA! ;)

whisperwhillow 11-10-2015 11:48 AM

So I filled up on propane; hooked it up and turned it on, of course; turned on the stove to bleed the lines a bit and make sure I had propane going through the lines; turned on the heat again. While heat comes out of the heater vents now, it's still pumping air (not sure if it's a/c or not because the air is chilly as it is) through the a/c vents.

I have turned it off and on many times; I have even taken the fuse out to reset the furnace. Still doing the same thing.


whisperwhillow 11-10-2015 11:59 AM

Well, this is embarrassing... Not a problem that I'm the only one responding to my inquiry lol, but I figured it out! The fan setting on the thermostat has to be set to auto to only run the furnace.

Whoever powers that be can mark this as closed.

Thanks for being a sounding board, FR forums! Till next time, happy (and warm!) camping! ;)

knockando 11-10-2015 12:08 PM

We've nearly had this exact issue all Fall on a Suburban furnace.

As for the air coming out of the AC vents make sure the Fan mode is turned to Auto. That should stop the air from coming out of the AC vents.

Our furnace seems to stop igniting (kicks on, fan runs for about 20-30 sec and then shuts off) when it gets a bit colder out. From what I can tell around < 38 deg F. When it warms up mid-morning > 38 the furnace operates properly. I believe I've isolated the issue to either the LP tank or the dual-stage regulator. I replaced the dual-stage regulator and we still had the issue.

From additional reading we think our LP tank tank has moisture in it causing the regulator to "freeze" up when it gets to a lower temperature. I have not gone any further but two things I've read:
- Have an LP company perform a purge of the tank to rid the moisture
- Someone suggested putting a heating blanket or something similar on the tank/regulator to prevent the freezing.

These comments come from experience and not an expertise so take them as you wish.

whisperwhillow 11-10-2015 12:18 PM

Wow, a lot of trial and error it seems! Thank you for the tips. If this continues, I'll definitely look into the purge or the blanket to see if it helps. Best of luck! ;)

knockando 11-10-2015 02:37 PM

Yes, 6 month old doesn't sleep to well when it's 50 in the camper :eek:

The piece that doesn't make sense is that the gas stove seems to be working fine during the issues with the furnace. I've also tried shutting off the gas at the tank, bleeding the line through the stove and then SLOWLY turning the gas back on. This only works sometimes. I've heard the furnaces are much more picky with gas pressure, etc. when attempting to ignite than stoves/fridges.

TGR 11-10-2015 06:10 PM

I too had furnace issues this weekend. My problem appears to be one of the LP tank regulators. I fixed my problem by moving my full tank to the other side of the RV, replacing the empty tank on that side and selecting the relocated tank for propane.

My stove worked and so did my water heater but the furnace would cycle through the 3-strike futility circuit and shut down. I could feel and hear the burners start but then go out. I also noticed a problem when I tried my water heater. The flame roared like I expected but I also heard some sputtering of the flame. When I exchanged my LP tanks all was well.

Apparently, there was enough gas pressure to run the water heater, albeit, with a sputtering sound, but not enough volume to run the furnace. If you are still having furnace problems, consider trying the fix I needed to get through the weekend.

Summer2Go 11-16-2015 05:22 PM

I have not really used the furnace yet. I tried to warm up the camper to clean, turned on a burner, and turned on the thermostat. Got cold air blowing like crazy. Then I smelled gas, so I turned it all off. Do you smell gas?

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TGR 11-16-2015 06:07 PM

Standing outside, next to the furnace, I could hear the igniter clicking and the flame start. There was also heat coming from the furnace exhaust for a brief time but then the heat stopped and only cold air came from the furnace exhaust. I could smell propane but only slightly.

Again, moving the full bottle to the other side fixed my problem for he night. I haven't investigated further.

TGR 11-19-2015 03:45 PM

I filled my empty tank and with warmer weather, my furnace works fine from either thank.

My guess is that one of my regulators was malfunctioning because water vapor froze and messed up my LP regulator or partially clogged my line from the one tank. The warmer weather melted the frost and all seems normal now.

I won't be using my trailer any more this year but if the problem reoccurs, I'll try purging my tanks or have methanol added.

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