No furnace and it's below 30ºF at night...

amkuntz

Member
We are having furnace issues and after reading several threads here, have not found the answer. The furnace in our 2011 Grand Canyon will only start if I take off the outside panel and flip the switch off, then on...it will then run until it reaches the set point. It will not run again until we go out and flip that switch...not nice to do at night when the grass is crispy.

We have tried lowering the temp on the controller until we hear a click in the A/C area, then turn it up again until we hear the click again. We have it set on auto for the fan. We have tried just pulling the fuse to get it to start, no luck there either.

Thoughts?
Marilyn
 

recumbent615

Founding MA Chapter Leader-retired
Marilyn,

Taking a shot in the dark here as I do not have a Grand Canyon - but is the Thermostat on Heat and not Cool? I made that mistake in the past ( once )...

Kevin
 

jbeletti

Well-known member
Marilyn,

Please call Suburban or Heartland Customer Service this morning. Both numbers are found on the portal page on the left side under Important Phone Numbers. Let us know how you come out.

Jim
 

brianharrison

Well-known member
Here is a document that has helped me in troubleshooting a RV furnace. Link. It has been shared on this forum previously.

Hope this helps some to understand furnace function and terminology.

However, I echo Jim's comments - Call HL or Suburban for help. Propane and furnace systems should be looked at by trained technicians.

Brian
 

randybest

Member
I have a 2012 bighorn 3070 and it has a Suburban furnace, Dometic thermostat. When I turn on the the furnace the AC runs also. I do not know how to stop this from happening. Anyone have an idea, this is my first 5th wheel.
 

wdk450

Well-known member
Randy:
I just finished doing a digital thermostat upgrade to my 2008 Bighorn, so I am up on thermostat wiring.
Your thermostat is just a complex electrical switch that completes an open circuit under the desired conditions. There is a cooling terminal and return terminal (the Y and RC terminals), a heating terminal and return terminal (the W and RH terminals) and 2 fan speed terminals for the AC fan function (GH and GL - these 2 terminals use the Cooling return terminal, RC, also). The Dometic AC / Suburban Furnace wiring uses a positive DC source in the AC Circuit board and Furnace circuit board that needs a GROUND on the control wire to enable the functions for those units. The thermostat needs +12 volts for its logic circuits and relay, so that is why the +12 volts is wired to the thermostat (Note that with the Digital thermostat upgrade which uses 2 AA batteries for power, the +12 volts DC red thermostat wire is no longer needed).
There is a switch inside the thermostats for heating systems that use an electric heating element on the AC cooling system for heat. To enable this function to work properly, there is a switch inside the thermostat with 2 positions labelled "HG" (Heating by Gas) and "HE" (Heating by Electric). This switch should be in the "HG" position for our RV's with propane furnaces. This switch in the wrong (HE) position might be your problem.
I went to check my old thermostat, a Duo-Therm model 3107612.008 for the switch. I didn't find it. It might be a wire jumper. It was certainly there on my new Hunter thermostat. But what DID happen shocked me!! I was pulling on the blue terminals strip where the wires from the heating/cooling equipments connect to the thermostat PC board, AND THE TERMINAL STRIP PULLED OFF EASILY!!! This terminal strip has 6 soldered connections to the PC board and NONE OF THEM HAD GOOD SOLDER JOINTS!!!
 

danemayer

Well-known member
I have a 2012 bighorn 3070 and it has a Suburban furnace, Dometic thermostat. When I turn on the the furnace the AC runs also. I do not know how to stop this from happening. Anyone have an idea, this is my first 5th wheel.

Change the thermostat fan setting to AUTO. When the fan is set to HIGH or LOW, it runs anytime the heating or cooling is turned on.
 

rvn4fun

Well-known member
We had furnace problems last winter, only time furnace would run was to turn thermoststat manualy on and off. Furnace would start then reach temperature and shut off. Would not cycle again unless you turned it off and on at thermostat. Once while furnace was running I tried to light the burner on the propane stove. Furnace quit right then. My problem was the propane regulator was set to low. Had service man adjust it and now everything works again.
 

kthwds

Member
Marilyn, i am also experiencing this problem in my new 275XLT.. it has happened in the past on my 2002 prowler. so i thought about what happened then. i looked at the regulator and WELL its the same it starts to frost up and slow propane down to where even the gas to the stove is really low. i am on here looking for hints or help as well. since i have two more weeks of hunting season to go and its getting below zero now... not that i recomend how i fixed the problem with the prowler "but" i ended up facing my generators exhaust in the propane cubby to keep frost off... it did work but the noise ;(
 

cookie

Administrator
Staff member
Hello Kthwds and welcome to the forum. Lots of good information here.
If you are experiencing icing in the LP compartmanet, how about putting a light bulb in there. Much quieter than a generator.

Peace
Dave
 

kthwds

Member
Dave thank you for the tip... i had thought of that when i was at the hardware store and seen the clamp on lights.. so i spent a couple -3 below nights in the hills and with a 75 watt mini halogen bulb pointing in the direction of the regulator also the place i by my propane suggested a cap full of heet gas line anti-freeze in the line before the regulator and shaazamm . NO problems. so be it the light or the heet, it worked.
 
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