Furnace puts out heat then shuts off

[Scott'n'Wendy]

Not sure of the accessibility of your hi temp and eco switch. Take a look and prepare a temporary jumper method.
Personally, I think the t-stat is more likely....but I've been wrong once or twice before....

[Petrovsky]

More cold weather on the way and we will be camping for 4 days so i will get a chance to do some of this troubleshooting

I carry a 16 gauge and 14 gauge jumper in my kit with alligator clamps on the ends for jumping limit switches. I have debugged the water heater,, a fridge, and last summer by gas fired pool heater with this technique in the past.

I have found the technique extremely useful finding the needle in the haystack so to speak. However, not as effective when you have an intermittent issue. Prior to jumping though, I disconnect and reconnect all terminal wires to ensure that no oxidation has affected the terminal connection.

[Alaska_av8r]

The cold front has not hit us yet, expected in about 5 hours, temps are appx 45 deg but furnace is working just fine so far.

[Firescue]

I have a 2020 2670MK and I had the same problem with my heater. My solution was to go to my neighbor who knows how to fix just about anything and maintained that title after fixing my fireplace. He removed the fireplace and found a silver heat sensor located at the top middle section of the fireplace. It's about 1/2 inch wide. Move it to the left (if you standing behind it) about 6 inches (maybe a little more) and give it a try. My fireplace has never given me a problem since. I did send a note to Grand Design and the lady said she will pass that on as it is a common problem. Just letting everyone know what solved my problem and I'm never moving away from my neighbor.

[LanerC]

IN OUR 2021 310 gkr, only after a few camping trips when new, the hi limit thermostat went out. The tech said it showed open when on the unit but showed ok after taking it off the furnace. one of those intermittent things. I replaced it with new and no problems since.

[Heavenbound]

Im having a similar issue in my 28BH. For those that have found a bad sail switch or a bad high limit switch did you have to "reset" the thermostat every time it kicked off? Mine will run and make heat for a few minutes then kick off. I have to cycle the thermostat off then on again to get the furnace to run again.

[bjlakatos]

OP-any resolution on this issue?

[LanerC]

Im having a similar issue in my 28BH. For those that have found a bad sail switch or a bad high limit switch did you have to "reset" the thermostat every time it kicked off? Mine will run and make heat for a few minutes then kick off. I have to cycle the thermostat off then on again to get the furnace to run again.

No, when my hi-limit switch went out the furnace never ran again until i had the switch replaced even if i cycled the wall thermostat.

[JimChow]

On YouTube search for 'MY RV WORKS". He has several troubleshooting videos on furnaces. It's a very good resource.

[Alaska_av8r]

OP-any resolution on this issue?

I have camped twice since then and not had a problem at all. That is very frustrating and hard to troubleshoot.

Tim