Urgent help, heater failed

Propane your out or very low...I HAVE BEEN THERE and done that...

I can't add anything to the suggestions posted, BUT!!!

We might be able to do still more, if we had Make and Model of the Furnace.

Chris Bryant's website (bryantrv.com) has a lot of manuals if you don't have the one for yours. Owner Manual probably has some troubleshooting, but Service Manual should have more detail.

Man does that sound familure.

Immed solution if you have electric is a space heater or two, However I do not like 1500 watt heaters on RV type outelts save for the washer/dryer outlet if so equipped.. Figure out a 12 gauge way to power them (I installed additional outlets that are of higher quality).

Second... I will append the Furnace Tribble Shoot guide to this but I suspect your control board.. That was my problem when it happened 5 years ago.. I went with a Dionsaur board from American RV in California (there are many American RV's the one in California had the part in stock about half the price of an OEM board and ... I was SERIOUSLY impressed by the quality, I'm an Electronics trained technician and hobbyist so when I say I'm impressed.. It's impressive)

Now for the boiler plate file

This document was created while I was diagnosing MY furnace.. I am told I missed one possible issue... Sadly I forget if I updated the document or not and the issue Bad connections anywhere along the line can lower voltage

When the T-Stat calls for heat the control board starts the blower (1)
The blower blows closing the sail switch (2)
The control board then opens the gas valve (3) and begins sparking (4.1)
Gas Flows (5) And ignitets (4.2)
The flame heats the flame sensor (5)
The flame sensor sends .480 volts to the control board (6)
which then detects the .480 and continues operation (*)
When the T-stat says "Enough already" (RV is now warm)
The control board shuts off the gas flow (*)
and then turns off the blower after a cool down (*)

*: At nearly every step the control board is involved. IF IT IS BAD, things will not work.. I recommend replacement boards from Dinosaur boards.. When Mine went out the Dino board was less than half the price and when opened the box the quality of construction and workmanship, and then design was very clear to my trained eyes.

1: No 12 volt to furnace, blower motor shot
2: Low 12 volt, air ducts clogged, blower "obstructed" bad sail switch
3: Bad solenoid, Clogged Gas Jet
4: .1: Bad ignition circuit (high voltage) on control board. .2: Points too wide (Very common it seems)
5: These do not often fail but they can
5: Bad connection, NOTE:
5 and * Bad wire.

* applies to all steps by the way So does bad wire/connection.

Roy is correct in that, if the sail switch contacts don't close, nothing else is going to happen. Can you hear the gas valve opening and the igniter sparking? The gas valve operating is pretty loud and you can usually hear it especially if you get close to the air return. If that is not happening, Roy is right and it probably is the sail switch not closing. If you do hear the gas valve open and the igniter sparking, does it light for a few seconds and then you hear the gas valve close with a "thunk"? If that's the case, the igniter electrode may not be sending a "proving" signal to the control board. Also, the contact on the wire from the igniter may not be making good contact with the terminal on the control board and cleaning it may fix it. If you have an Attwod furnace, this is easy to check and fix from the outside. If you have a Suburban, all the guts are inside the furnace and you have to find a way to get inside it to fix the problem.

I had to clean the burner and igniter on the Attwood in my previous trailer and it was easy; I just hope the Suburban in the current trailer never acts up!

This was a long winded explanation but I hope something in it helps you get some heat. Being cold stinks.

Happy Thanksgiving,

Ken

Maybe the obvious? Are you out of propane? Did you remember to turn your propane tanks on?

Turn thermostat off/on and try several times .
Might call mobile tech or fellow RVer to help you.
As Roy mentioned, there are a number of factors.

Call me. I can help you.

Usually the 12VDC fan has to work to keep the sail fan in the ON position.. IS that happening... This is a safety feature to shut down the propane furnace in the event the DC Fan quits workings... Might need to WD40 the sail fan some... 12VDC DC also runs the thermostat...

I am assuming your propane tank is feeding the main kitchen stove burners OK... All burning nice clear blue flames right... Red Orange color means you have an air leak in propane line... I always ran the burners first before turning on the propane heater to make sure I have propane haha...

My older trailer has the propane tank select switch. I imagine the newer ones is auto select

If both of these are working then it has to be obstruction in the propane line somewhere... Spider webs, rats nest around the sail switch is what alot of folks fine etc... Insects/Wasps crawl in from the hot air cover outside.

I'm sure your trailer also vents heat from the propane furnace towards the water tank... being down in the 20's might freeze that up if the furnace is not working...

just some of my thoughts...
Roy Ken