Furnace works intermittently

[Flyphoto]

2022 FR 261bhxl, furnace worked perfectly when new. Now, it will work fine sometimes, and then will quit working with no rhyme or reason. If I turn off the thermostat and then turn back on, it will sometimes work fine again. Sometimes I have to turn it off and back on several times before it starts to work again. When it doesn't work, the fan comes on an stays on for a long time. I can hear the furnace make a loud click and can hear the gas light, but I think the flame goes out because I hear the same thing again a few seconds later. Eventually, the furnace will fire up and work fine, but then it will just be the fan blowing and no heat. I then have to shut it off at the thermostat and try again. Lastly, when it quits working, the fan keep blowing even for quite a while after I use the thermostat to turn it off. Can anyone help?

[jjscsix]

What are you setting the fan to at the thermostat, High, Low or Auto?

[Flyphoto]

No option for fan when in heat mode. It's just set to heat.

[5picker]

Tell us the make/model of your furnace and do you have a stand alone thermostat or is it controlled by something like a Firefly digital control center?

Not all R/Vs have the same furnaces or controls.

[Flyphoto]

Suburban is the brand, but I can't see a model number. It's under the jacknife couch with 3 vents coming out from under the couch, separate from the AC which is in the ceiling.

[Flyphoto]

Thermostat controls the AC and the heat, it's an Air Xcel.

[Flyphoto]

I can hear the gas being lit, but it must be going out for some reason. What would this point to?

[markb5900]

First thought for me would be the flame sensor since you said it does lite.

[Bob K4TAX]

I would also check the outside vents for the furnace. One is the combustion air intake and the other one is the combustion air exhaust. Often wasps and spiders like those places. Remove the screws on the outside cover and examine the tubes using a strong light. Clear any debris, critter nests etc.

Bob

[Ryanweaver]

I have a 2013 surveyor sp220. Cold weather came around and furnace not working again. Checked for power in a few different places and its getting power everywhere I checked. Turned it on by mistake a couple months ago and it came on but bow that its getting cold I tried it and no dice. Then a week ago I started hearing a weird noise and found it was the fan relay clicking the fan on and off over and over without the thermostat even being on. Does this sound like a circuit board fault?

[TGR]

If you can hear the burner start and then shut down a short time later, it might be the trailer's gas regulator isn't providing enough gas volume to keep the furnace operating. It could also be the furnace's flame sensor is dirty or defective and, of course, it can be the motherboard is defective.

There is a 3-strike futility circuit that stops the restart cycle. Power the furnace off and that circuit is reset for another round.

[Flyphoto]

Here is what I found: It was a loose wire- one of the two brown wires that go to the Gas Valve. It appears that one was just barely connected which created the intermittent condition. I put it back on and tested many times in my garage, then reinstalled the furnace in the TT and tested many more times. It seems to be working fine.

[ppine]

Mine quit once after a desert sand storm. A tech blew out the valves and fittings with compressed air and it worked fine.

[Capacitor]

Ryan weaver. You may want to start your own thread .

[Scott Holland]

Just had to replace blower in mine. Only 1.5 years old. Would start up then shut down after 30 seconds. Not spinning fast enough to activate switch in blower housing. Still jumping through hoops trying to get covered. It’s a Suburbab SF35VHQ