Ready to go camping...except: furnace won't fire

[SubliminalME]

Hey all, I have a 1993 Fleetwood Wilderness with an Atwood Hydro Flame furnace. I can't get it to light. I watched some videos, and made sure it was getting power.

I can trace the power to the time delay relay, and see power on several of the leads, but not on the output that turns the fan on, etc.

I tried to jump the power to the output, and the fan fires right up, but I read that I should be getting clicking from the ignitor, but no...when i jump it, the fan runs and thats it. I am getting ~12-13 volts into the thing, and when i jump it, its the same voltage out.

I tried to call the previous owner, but they were no help.

I can't see any type of pilot light setup, i believe it's strictly light-on-demand.

Can anyone provide any help?

I'm getting desperate...and been racking my brain for hours on this.

Thanks!

Damon

[ppine]

RVs have systems not like a residence. They can be confounding. Find an RV tech that comes to your house.

I rarely use the furnace. I like to boondock and use a Little Buddy once in awhile or just make coffee.

[TenOC]

One year my furnace would not light and I found out that paper wasp have built a nest that blocked the fan from turning. Just a thought that you might want to check out

[BFL13]

Should be two wires coming in from the furnace to the Tstat. Jumper them and it should fire up after the usual delay. The Tstat just jumpers those wires when set to want heat.

I got a digital Tstat that is for heat only. Put one wire to R and the other to W and you are good to go.

The two wires are just the one wire cut there so it can be switched.

[SubliminalME]

Definitely the thermost. I can tap the thermo and it will come on. Sometimes stays on, sometimes turns back off. but it's definitely at the thermo.

[morphrider]

Look at the vent outside and make darn sure no hornet has built anything in there. We had a pop up for couple years and I fought with the no light issue until the day I sold it, literally. It had 1 small blob in there I removed, fired right up after that.

[Travelin2]

When the fan starts it has to lift the "sail switch". If the heater has not run for a long time the sail switch could be stuck a bit. Work your way into the fan discharge and move the sail switch manually back and forth to make sure it swings freely. Nothing other than the fan will operate if the sail switch is not activated.

[BFL13]

I have an 8531-ll with some -lll parts thrown in, and have had some issues getting it all going properly, but finally got there (thanks to good help on here!)

You are not clear on where you are measuring the power or jumping -- where your multimeter set to voltage probes are for these readings.

Start with the thermostat. When it is set to want heat, is there 12v down at the furnace ? where exactly? Then where?

One step at a time will get us there and your furnace working, but clarity is important!

[SubliminalME]

ksg5000 wrote:
RV furnaces won't fire up until the squirrel cage fan moves at high speed (that won't happen with low battery). Check RV battery or connect to AC power - might rule out one possibility.

I installed a brand new battery yesterday, and have it currently plugged into the house. Thanks for the reply, though!

[SubliminalME]

Ok, i watched some more Youtube, and a video showed a guy jumping from the output of the fuse/circuit breaker (mounted at the furnace) to the thermostat input on the time delay switch, and she fired right up like she should.

So..I guess that means either thermostat or wiring between thermostat and furnace?

[ksg5000]

RV furnaces won't fire up until the squirrel cage fan moves at high speed (that won't happen with low battery). Check RV battery or connect to AC power - might rule out one possibility.

[SubliminalME]

It's a hydro flame 8531-II