Lazy Daze Owners' Group

Lazy Daze Forums => Lazy Daze Technical => Topic started by: T&F on November 02, 2019, 05:11:30 pm

Title: Suburban Thermostat Off Switch Failure
Post by: T&F on November 02, 2019, 05:11:30 pm
We have a 2014 MB with a Suburban Furnace.

Back in July we ran the furnace in the morning to warm up the coach a bit, and then moved the thermostat switch back all the way to the left to shut it off, but this had no effect.  We ended up having to pull the fuse from the 12V side of the main panel to shut it off.

Anyone else have this problem?  I'm currently scoping out the technical info online to see if I can get some procedures to isolate the problem.  Will report back if I find anything out.

Thanks,

Tim
Title: Re: Suburban Thermostat Off Switch Failure
Post by: Kenneth Fears on November 02, 2019, 05:59:35 pm
The thermostat has a "slide" portion and an "Off" position.  If you slid the tab to the left until it stopped, but not far enough for it to click, you did not get it to the "Off" position.  If you felt the click as you slid it to the left, and it kept running, that sounds like a thermostat failure.

Ken F in NM
Title: Re: Suburban Thermostat Off Switch Failure
Post by: T&F on November 02, 2019, 06:41:36 pm
Ken,

Yes, we slid it all the way left and clicked it into the off position, so I agree that it seems like a thermostat failure.

Thanks,

Tim
Title: Re: Suburban Thermostat Off Switch Failure
Post by: Steve on November 02, 2019, 07:14:48 pm
After turning off the furnace at the thermostat, the fan will continue to run until the flue temperature falls below 300F, which can be a couple of minutes. The flame, however, should extinguish immediately.

Steve
Title: Re: Suburban Thermostat Off Switch Failure
Post by: colddog on November 03, 2019, 09:30:34 am
The thermostat has a "slide" portion and an "Off" position.  If you slid the tab to the left until it stopped, but not far enough for it to click, you did not get it to the "Off" position.  If you felt the click as you slid it to the left, and it kept running, that sounds like a thermostat failure.

Ken F in NM

Or a broken switch.   This happened to us around the first couple of times we used the Suburban.

glen
Title: Re: Suburban Thermostat Off Switch Failure
Post by: T&F on November 03, 2019, 12:34:02 pm
Steve,

Yes, that's right: however, the gas was not shut off, so this was definitely a problem.

As Ken mentioned additionally, the switch actually broke on him.  I'm going to try a test to further isolate the problem.

Tim
Title: Re: Suburban Thermostat Off Switch Failure
Post by: JonS on November 03, 2019, 03:31:14 pm
Take one of the wires off at the t stat, gas should go off.
Title: Re: Suburban Thermostat Off Switch Failure
Post by: snerf on November 04, 2019, 06:20:15 pm
Take one of the wires off at the t stat, gas should go off.
Or remove the fuse - like they did - to achieve the same effect. The switch on our 1993 was really primitive. It would be easy to see it breaking and or jamming an internal short.

I'm guessing RV thermos are getting to be like home units with more electronics. My motto was always to swap and forget - within reason. That is, I'd rather spend $30-40 bucks for a replacement part if I couldn't immediately detect what was malfunctioning.
Title: Re: Suburban Thermostat Off Switch Failure
Post by: Eric Greenwell on November 04, 2019, 11:15:25 pm
I'm guessing RV thermos are getting to be like home units with more electronics. My motto was always to swap and forget - within reason. That is, I'd rather spend $30-40 bucks for a replacement part if I couldn't immediately detect what was malfunctioning.
You can get digital thermostats at Walmart, Home Depot, and elsewhere for only $20-$25, and they work better than the old style mechanical thermostats, keeping the temperature within one degree or less of the setting, compared mechanicals 2 degrees or more. That smaller temperature swing means noticeably more comfort when heating.
Title: Re: Suburban Thermostat Off Switch Failure
Post by: T&F on November 10, 2019, 08:49:07 pm
FYI, I ended up purchasing a new Suburban (White-Rodgers) thermostat from Amazon ($19), identical to the old one.  Installed it and it works fine.

Thanks for all of your replies.

Tim
Title: Re: Suburban Thermostat Off Switch Failure
Post by: krmugn on November 10, 2019, 11:43:34 pm
The best outcome. Fixed the problem for less than $20 bucks.  It's rare, but thermostats do fail. Especially an old style thermostat. They're almost bullet-proof!

Bill