Any suggestions on an inoperative furnace?

[Barko1]

Before I drag it to the local RV place I thought I'd fish for an idea or two. Was working early in my trip last week but then nada. Turn on the thermostat and it seems to call for heat but no ignition. I have propane, at least the range burns and the fridge runs.Looking at the manual it seems there are many possible issues that need testing or is there some magic bullet?

 

[pods8]

Are the fans turning on and you're just not getting ignition or is the furnace not even firing up?

If its not firing up do a few "duh" checks:
You have 12v power on/available?
Fuse blown for furnace?
If those two pass then check to make sure thermostat is still working, hold a jumper wire across the two furnace wires in the thermostat to complete the circuit to rule out the thermostat.

If your just not getting ignition I haven't dug into the furnance at all to know any specifics but I'd guess your ignitor is either worn out or got rattled or such so its not sparking properly.

 

[Jack]

I assume you have an Atwood.

First of all, make sure you have a charged battery. The fan will come on, but if there is not enough flow, due to low voltage, the furnace will not attempt to light.

The Atwood turns the fan on for 10 seconds, then turns on the igniter for a few seconds - you can hear the clicking of the spark. If the burner does not light, the Atwood keeps the fan on for10 seconds later makes another attempt to light. If a third attempt fails, the fan stays on for another 10 seconds and then turns off.

There is a red LED on the circuit board at the top of the unit - you can see it if you take the back cover off. If the circuit board detects a fault, the LED will blink in one of several sequences that are describes in the manual.

Finally, check the wiring to make sure a wire has not come loose. In particular, re-crimp the T connection (the connector that crimps onto a continuous wire and then crimps onto a third wire in a T fashion) that is right in front of the unit behind the back cover. I've never liked these kind of crimp connections and the one on our Atwood had to be re-crimped.

 

[dsrtrat]

Atwood ault

If the furnace fails after three attempts to light it goes into a default setting that requires the thermostat to be cycled off and back on before it will try to relight.
I have had problems with mine not wanting to light in very cold weather, it sometimes takes more than one cycle of three before it fires.

Dsrtrat

 

[Brewery Meister]

I had a similar problem last summer...

And I brought it to Marty. He found that everything inside was rusted. I live by the ocean and hadn't used the furnace in a while. You might want to check the rust/call Marty.

Clark

 

[Stan@FourWheel]

Hey Barko

Watching your postings over the months, I bet you can get it going yourself (at least there is a good chance of it).

On the older campers, I would say 80%-90% of the time, if the furnace fan is running, but the furnace is not lighting up, there is nothing major wrong with the furnace. I'm not an RV service tech, I can't build anything, but I can usually tinker long enough to get things going.

Try this before taking it in ...

1. Take off the furnace vent covers inside (on the cabinet).

2. Take off the outside furnace cover.

3. Take some compressed air, air hose, or something like this and give it a good whirl around in there to get out any debris, dust, spider webs, etc.

4. Usually when you remove the furnace covers you can see, or might find a small toggle switch burried inside there somewhere (use a flashlight). Reset the switch a few times (turn it on/off), but always make sure you leave it in the original position where it was set.

5. Wiggle and giggle the wire connections around to make sure there are no loose wires or corroded / rusty wire terminal connections.

6. If you can get to it, give a quick spray of silicone on the shaft of the blower fan inside there (just so the fan can turn as smoothly as possible).

7. Like someone else mentioned, make sure your camper battery / batteries are fully charged up.

8. Make sure your propane tank is full, or at least not empty.


Most of the time this should get er' going.

Again, this is not FWC service advice, just personal advice from me to you.

If in doubt on anything, always consult a trained professional.




Hope this helps !


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Before I drag it to the local RV place I thought I'd fish for an idea or two. Was working early in my trip last week but then nada. Turn on the thermostat and it seems to call for heat but no ignition. I have propane, at least the range burns and the fridge runs.Looking at the manual it seems there are many possible issues that need testing or is there some magic bullet?

 

[Barko1]

I forgot what brand it is, 96. Tried it out againtoday in a quiet environment, pushed up the thermostat, fan started, then burner fired and all was operating normally. I think I have had plenty of voltage. Tank had a couple of gallons in it. I wonder if the valve from the tank wasn't fully open and therefore not enough gas? Probably not but it seems fine now, I'll test it a few more times, do the spider blow out and try to squirt some lube in there. Heading to Alaska in 2 weeks and will want some morning heat. Today the propane read 1/4 when horizontal, 1/2 when I pulled it out, and it took 3 gallons when I had it filled.

 

[ScottBailey]

Last trip out, my thermostat's connections got loose, but not completely... Effect: the fan would start from a brief connection, but never fired.

Fixed it and learned to stack boxes only so high, so they can't bang into the thermostat while traveling.