Furnace Question

[roadrat57]

Hi all!
Took my first camping trip with 32' Fleetwood motorhome. Temps dropped to 26. Furnace would fire up and warm things up but would start backup 45 seconds after completely shutting down. It was running continuously except for the 45 second breaks. Doesn't make sense. Most of the heating vents are from the thermostat back to the bedroom and bath. Only one vent under kitchen counter for the entire front half of the coach. Furnace ran normal until early morning temps dropped below 32.

Any ideas?

Thanks

[Joe417]

I had an issue years ago where the furnace did something similar. The furnace just couldn't keep up and it was only about 30 degrees with a stiff wind. It would cut off and then back on in a short time.

I took the furnace apart and found that more than half the holes in the burner were fill with dirt dauber mud. Cleaned it and installed insect screens on all openings. Issue solved.

Since then I have screened and sealed all opening on every camper we've had as soon as I could get it done.

[BFL13]

If you have a digital thermostat, it will try to keep the temp from dropping more than about one degree before restarting the furnace. An analogue thermostat will let the temp drop more before kicking the furnace back on. Sounds like you have a digital stat.

[Lwiddis]

“while saving propane“

Propane is inexpensive and available. “Save” somewhere else.

[roadrat57]

Thanks

[rhagfo]

roadrat57 wrote:
Noticed ceiling ac vents have the ability to be closed. This would save heat, would it not? Does heat escape through such vents?

AC is a closed system, it just recirculates air in the MH, no outside air.

[roadrat57]

Noticed ceiling ac vents have the ability to be closed. This would save heat, would it not? Does heat escape through such vents?

[roadrat57]

Thanks to all of you for your comments. My plan will be to close off the hallway containing the thermostat, bath and bedroom while allowing the open living room and driver area to rely on the lone output vent. This should keep the sleeping area toasty while saving propane and preventing the need for the furnace click on and off so often.

Roadrat

[rhagfo]

1st quest what temp were you trying to heat to? We find that 68 degrees is very comfortable. with that last January we were hosting at the coast. We were very comfortable in our 32' three season 5er, at 20 degrees using the Cheap Heat system , which is only 5,000 watts of heat or 17,600 BTU. Our gas furnace is rated a 30,000 BTU input, or 24,060 BTU output. The cheap heat system didn't run anywhere near constantly.
You either have a huge cold air leak, a very weak furnace, or trying to heat to about 75 to 80 degrees.

[wa8yxm]

The furnace cycle, you might not notice this but the blower starts.. Then later the BURNER starts.. shut down is in reverse order, the blower blows for quite some time after burner shuts off so your "Down time" is skewed. it is actually much longer.

Second, you are getting right close to the low-temp limit for your RV, so near constant furnace operation is normal.

[time2roll]

Probably restricted or inadequate ducting. You need to improve the hot air ducts or add more.

[naturist]

Sounds to me as though you were operating very close to the minimum temperature at which your rig's furnace could provide the heat needed to keep you warm. It got down to 26 and you had 45 second off time, so I bet had it gone to 24 or 25 the furnace would have simply run continuously.

So, if you intend to use it during even colder weather, plan to get one or more extra heaters. Alternatively, just don't use it below freezing.

[1492]

Moved from Forum Technical Support

[corvettekent]

Get a Big Buddy heater and a hose. They work so much better and use a lot less propane than your furnace.

[donn0128]

At 26 degrees and not knowing the BTU output of the furnace or what temp you had it set for, I would say totally normal