Heater Stopped Working

[62cowboy]

We're having a cold spell so I plugged in our 19-G to our garage outlet to run the heater for a few minutes. Yesterday it worked fine, but today it doesn't heat and the fan doesn't even come on. The breakers weren't tripped. The manual doesn't provide much troubleshooting info. Any suggestions?

[Scubawise]

propane tank open and full?

[EA37TS]

Originally Posted by 62cowboy

We're having a cold spell so I plugged in our 19-G to our garage outlet to run the heater for a few minutes. Yesterday it worked fine, but today it doesn't heat and the fan doesn't even come on. The breakers weren't tripped. The manual doesn't provide much troubleshooting info. Any suggestions?

Did you plug into a GFCI outlet? Rigs sometimes don’t like GFCI to GFCI connections and will trip the GFCI outlets.

[16ACE27]

Your furnace runs off 12 VDC so plugging in is not necessary except to keep the batteries charged.

So you are plugged in now:
Does your microwave work?
Of so, you are getting 120 VAC into the coach and your converter should be working to supply 12 VDC to the DC buss - time to troubleshoot why you aren't getting 12 VDC to the furnace.
If not, time to troubleshoot why you are not getting 120 VAC into the coach. It could be a tripped GFCI outlet/breaker (common issue) or the supply breaker for the outlet you are plugged in to in the house's breaker panel.

[62cowboy]

Hi again - Propane is on and working (able to turn on the stove burners), I'm not plugged into a GFCI outlet; microwave works. And it worked fine yesterday. Is there a fuse associated with the furnace that I could check? How can I tell which fuse is for the furnace?

[16ACE27]

Good info! Now we know which way to troubleshoot.

The furnace receives 12 VDC from the fuse (DC) side of your power panel. If you look at the list of fuses, one of them should say something like "Appliances" as the same fuse many times supplies control power for multiple appliances like the furnace and fridge, but not always so we won't use those for troubleshooting.

Once the power gets to the furnace it hits the On/Off/Reset switch. You may just need to take the outside cover off the furnace and "Reset" that switch to fix your problem.
That same power goes to your thermostat and is used to tell the A/C and the furnace when to cycle on. If you have enough SP you can run your A/C to verify power to the furnace and up to the thermostat.
Having a multimeter and knowing how to use it will help you in your troubleshooting as will the "wiring" diagram for your coach available at the Thor Owner Resource center.

A common furnace problem is the control board getting wet in a heavy, blowing rain. Does this apply?

[Beau388]

Originally Posted by 62cowboy

Hi again - Propane is on and working (able to turn on the stove burners), I'm not plugged into a GFCI outlet; microwave works. And it worked fine yesterday. Is there a fuse associated with the furnace that I could check? How can I tell which fuse is for the furnace?

You don't need to search for a fuse in the power center. The propane furnace supplies 12 volts power to the thermostat. Turn the thermostat on to cool and turn the fan from auto to on. If the A/C fan comes on, you have 120 volt to the A/C and 12 volts to the thermostat. If the A/C fan does not come on now is the time to search for a fuse in the power center. Most modern power centers have a telltale light associated with each fuse. If the A/C fan did come on, select heat on the thermostat and set the thermostat temperature so that furnace should come on. If the combustion fan does not come on you have a circuit board problem.