Gas Furnace not working...need suggestions

[smlranger]

OK, I expected something to break on the trip...my gas furnace will not come on. I've checked the furnace breaker and it is OK...gas OK because all other gas stuff works fine.

I suspect the dang, cheap, Coleman thermostat which I replaced ($145) in Myrtle Beach this past Feb.

Anyone got any thermostat troubleshooting tips? Can this thing be replaced with a good residential thermo?

[smlranger]

OK, I expected something to break on the trip...my gas furnace will not come on. I've checked the furnace breaker and it is OK...gas OK because all other gas stuff works fine.

I suspect the dang, cheap, Coleman thermostat which I replaced ($145) in Myrtle Beach this past Feb.

Anyone got any thermostat troubleshooting tips? Can this thing be replaced with a good residential thermo?

[troth]

My quick search here found posts that said the Coleman t-stat is problematic. Someone said to ensure the slide switches are truly in the heat detent position (slide firmly through cool, off, then heat).
I recall other posters talking about the ease of using the Hunter t-stat as a replacement. Look at this thread:
Ken Lenger's thermostat change
They say the Hunter unit was good-to-go if it was all powered by self-contained batteries.

[Kazoo Tom]

You might also try Bryant RV web site. Once there to the service documents page. If you know the make and model of your furnace the complete service manual for it may be available there for download. Hope this helps.

[rebelsbeach]

Hey Gary....if all else fails....drive to where it's WARMER!!

["007"]

X-the wires to t-stat to see if burner comes on, if yes bummer t-stat.
A good house t-stat should work you only need the thermal spring in t-stat to close the contacts for heater to operate.

[smlranger]

I checked the fuse in the thermostat and it is fine. So I tried again...when I set the temp to call for heat and switch to Gas Heat, I do hear the thermostat click. That is making me think I have a problem with the gas furnace. If we travel near a Winne dealer, we may stop and see if we can get service. Otherwise, I may wait until we get home and see my friendly independent RV guy.

[Dave from MN]

The first thing to come on is the fan. If not, it will not light! There is a switch that is activated when the fan is going. It is called a sail swich, I believe. I have had more trouble with that switch. I just take the cover off & spin the fan or monkey with the switch. It will work until the next season! It is always working when I think about having it looked at! Funny thing, it only happens in New Mexico!

[RVDriver]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">It is called a sail swich, I believe. I have had more trouble with that switch. </div></BLOCKQUOTE>

Right Dave, the Fan comes on, this blows on the Sail Sw, the SW makes, saying the fan is running and clearing out any gas fumes before the furnace tries to lite! There have been many bad "Sail Switches"!

Bruce

[smlranger]

I called my home base RV guy and he talked me through a few checks. If I bypass the True Air thermostat and jump the furnace wires, all I get is an audible click in the area of the furnace...no blower, nothing. So, looks like the new thermostat RVP is overnighting to me here in CO won't do it.

I crawled under this beast but I just cannot determine how to access the furnace wiring, etc. We're probably going to be in climates where the heat pump will do fine so will likely wait until we're home and let my guy have at it.

Just out of curiosity, does anyone know how you access the furnace on a Journey of this era? Mine is just behind the right rear wheel slightly above the HWH.

[Joe-K]

Gary,

I'm not home to look at my furnace now, but the last time that I worked on one for a friend, I found it wouldn't run because the blower was stuck after not being run for a long time.

All I had to do on that unit was turn the blower a bit by hand and it started right up. On that unit, I had disassembled the furnace, but may you don't need to.

I might get a couple "You're nuts " comments for suggesting this fix, but since you're in a middle of a trip, it might work.

First, make sure the furnace is turned off then get a piece of fairly stiff wire (a coat hanger might work) and bend it in a large radius curve. Carefully pass the wire into the burner from the outside of the motorhome and try to rotate the blower by usig a wire. If you're able to rotate it, you might be surprised and the furnace might work.

No guarantees, but it's worth a shot to avoid pulling the furnace out. If it doesn't work, Joe and his coat hanger repair is going to be laughed at for a while.

[troth]

Gary, maybe a long shot but worth saying:
A.) make sure the house batteries are up and fully charged. The furnace blower needs a solid 12vdc to run.
B.) I'm thinking that disconnecting the wires at the thermostat won't do anything for you. You need to test where the thermostat wires come into the furnace control board. You should see continuity or possibly low voltage (up to about 3 vdc there) from the thermostat batteries when the thermostat is "calling" for heat.
C.) One last thought... See if you can find a strong +12vdc power coming through a heavier wire (like 12 or 14 ga.) to the furnace. Use a awl-type probe test light and pierce thru the different wire's insulation if needed). If no primary 12vdc is coming to the furnace, you've got a big fuse, or likely a resettable circuit breaker, that popped.

Keep us posted please.

[smlranger]

Tom:

I'd be happy to do those tests (I have both an automotive light probe tester and a voltmeter) but I cannot find any access to the furnace under the rig. It is sandwiched between the rear wheel and the water heater and I cannot see any access.

Thanks for the suggestions.