Print Page - Furnace fan won't start

Title: Furnace fan won't start
Post by: Dave Miah on November 20, 2017, 11:56:55 am

Yahoo Message Number: 16344 (http://groups.yahoo.com/neo/groups/supercrvgroup/conversations/messages/16344)

Hi Everybody - my rv is a 2005 Gulfstream Endura and the furnace fan won't come on when I turn the thermostat on. If I jumper 12 volts directly to the motor the fan starts up and the furnace will make heat and even be controlled by the thermostat.

I put a new circuit board in it, but still no luck.

Any ideas???

Title: Re: Furnace fan won't start
Post by: Dave Miah on November 20, 2017, 11:58:09 am

Yahoo Message Number: 16345 (http://groups.yahoo.com/neo/groups/supercrvgroup/conversations/messages/16345)

By the way it's a Suburban SF-35 model.

Title: Re: Furnace fan won't start
Post by: Ron Hall on November 20, 2017, 12:24:31 pm

Yahoo Message Number: 16346 (http://groups.yahoo.com/neo/groups/supercrvgroup/conversations/messages/16346)

Bad Thermostat. That's my guess. I have 2 of the original Duo Therm thermostats that I took out of my MH. There yours if want to come and get them.
What are you hooking 12 volts too?
Best
Ron Hall

Title: Re: Furnace fan won't start
Post by: Britton Julien on November 20, 2017, 12:39:21 pm

Yahoo Message Number: 16347 (http://groups.yahoo.com/neo/groups/supercrvgroup/conversations/messages/16347)

I also believe it is most likely a bad thermostat.

Title: Re: Furnace fan won't start
Post by: Doug Scott on November 20, 2017, 02:10:45 pm

Yahoo Message Number: 16348 (http://groups.yahoo.com/neo/groups/supercrvgroup/conversations/messages/16348)

Hi Dave,

I'am not a mech but three things do come to mind.
1) rodents can gain access and possibly chew thru wires.
2) by placing a jumper, you may be circumventing a breaker or a fuse or both..
3) also with a jumper you could be nulifying a built in safety control associated with the propane system.

Title: Re: Furnace fan won't start
Post by: Dave Miah on November 20, 2017, 02:23:16 pm

Yahoo Message Number: 16349 (http://groups.yahoo.com/neo/groups/supercrvgroup/conversations/messages/16349)

The jumper was just a test method to see if the blower motor worked. Thanks

Title: Re: Furnace fan won't start
Post by: TJ Kennedy on November 20, 2017, 10:04:10 pm

Yahoo Message Number: 16350 (http://groups.yahoo.com/neo/groups/supercrvgroup/conversations/messages/16350)

There is a normally open time delay relay that is being jumpered. Replace the relay

http://bryantrv.com/docs2/docs/SFseriesservice.pdf (http://bryantrv.com/docs2/docs/SFseriesservice.pdf)

Found a wiring diagram on above web site.

Title: Re: Furnace fan won't start
Post by: Dave Miah on November 21, 2017, 11:41:34 am

Yahoo Message Number: 16351 (http://groups.yahoo.com/neo/groups/supercrvgroup/conversations/messages/16351)

This one doesn't have a seperate relay. Turns out that after we replaced the board, we bent one of connector's pins so it wasn't making contact.......

Title: Re: Furnace fan won't start
Post by: Ron Hall on November 22, 2017, 06:19:48 am

Yahoo Message Number: 16352 (http://groups.yahoo.com/neo/groups/supercrvgroup/conversations/messages/16352)

Glad you got it fixed.
Best
Ron Hall

SuperC RV Group

Super C RVs => SuperC Info and Discussions => Topic started by: Dave Miah on November 20, 2017, 11:56:55 am