Furnace

1kotonk

1kotonk

Senior Member
Joined
Sep 28, 2016
Posts
153
Location
Los Angeles. CA
Ok, I have a 2008 136x, I cant get the heater to turn on. Was working good the night before. Iam staying at a spot with full hook ups. I have propane, checked all fuses, unplugged the shore power and tried with just the 12V. Nothing. No fan or ignition clicking. Everthing else works.

It was 38 degrees last night, lol.

Any suggestions for a quick fix?
 
Has it worked before, like at home?

If it used to work but does not, my first thought is a fuse. I know you have checked the fuses, but they are often difficult to see -- in my 2012 X-139, the fuses are those little plastic things that look like this:


m3zZPvb.png
Click For Full-Size Image.

I have found that I have missed breaks in those fuses unless I hold them up to a light, which is a pain in the neck. Plus, it is hard to pull them out of those sockets and put them back.

You can get a fuse puller at an auto parts store. Don't use a needle-nose pliers. It can break the fuse. Don't ask how I learned this.

If it is not the fuse, it could be the thermostat -- unlikely, but possible. It is easy to replace a thermostat. I do not know how to diagnose a bad thermostat -- it would probably involve a continuity meter. Those are inexpensive, but I don't know how to use one. I bet youtube would teach you how.

Hang in there! 38 degrees inside a trailer is chilly but not impossible -- we do that all the time when we are snow-camping. Lots of blankets, lots of warm clothes.
 
Thanks ProfDant,

Lol, yeah I've seen how you camp. It's almost embarrassing for me, compared to the snow you guys boondock in. I am at Silverwood Lake doing some fishing. Three days of fishing and no luck. It's still better than sitting at home. I like it out here to bad its 50 bucks a day. I would come out here more often.

I checked all the fuses with my meter and they are all good. My trailer uses the same fuses as yours. If you look at the numbe printed on the fuse, you'll see two tiny holes, you can stick the probe tips there to check continuity with out pulling them out. But that's about as far as my electronic know how goes.

I believe it's some type of relay in the circuit board on the furnace. The board is a pain to get to, its like working in the engine bay of my Honda.
 
You are way ahead of me -- I had no idea that I could check the fuse with a meter, without pulling each one out and looking at it. Thanks for the tip!

Good luck with the circuit board -- I did not even know that there were any consumer-serviceable components on it.
 
1kotonk said:
Ok, I have a 2008 136x, I cant get the heater to turn on. Was working good the night before. I am staying at a spot with full hook ups. I have propane, checked all fuses, unplugged the shore power and tried with just the 12V. Nothing. No fan or ignition clicking. Everything else works.

It was 38 degrees last night, lol.

Any suggestions for a quick fix?
Click to expand...

All of the trailer thermostats I have seen are just 2-wire switches in terms of how they operate. They open the circuit above a certain temperature and close it below that temperature. You could short the two wires together to see whether the thermostat is the culprit but it may be the control board which probably has a interlock relay to make sure that the fan comes on before energizing the igniter and opening the gas valve. Very old furnaces had pilot lights but the newer ones all have a spark igniter to start the flame.
 
Here are a couple of typical wiring diagrams of Suburban furnaces.

Hope the fishing is better!
 

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    Furnace wiring diagram.JPG
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Thanks Jimbo. I believe your right, I did jump the circuit but as soon as the fan started I took the wire probe off, it ran for about 10 seconds and turned off. Today researching on utube I learned it's most likely and bad contact in the thermostat.

I ordered a Honeywell digital heat only thermostat it's like you said a two wire installation.

I'll post a follow up to let everyone know the outcome.
 
If it is similar to Honeywell TH1100DV1000 it sounds like it will work according to Amazon comments. You had a novel idea! Thanks!
Question: Will this unit operate on a 12 volt RV electrical system without the aaa batteries installed? Will the display be readable?
Answer: No, I tried this. You need the batteries. They last about a year. It does control the 12 Volt RV furnace properly when the batteries are installed. The temperature control is greatly improved versus the standard RV thermostat.
By Wires 89085 on May 2, 2020
Answer: The AAA batteries power the display
By Jeep Guy on November 9, 2018
 
I read on Amazon that Honeywell makes a digital thermostat that will control RV heaters and furnaces (according to several reviews). I haven't tried it so you can be the guinea pig on our FF forum. There are even YouTube videos of how to connect it to a RV!
Honeywell TH5110D1006 Honeywell Non-Programmable Thermostat
 
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1kotonk said:
Ok, I have a 2008 136x, I cant get the heater to turn on. Was working good the night before. Iam staying at a spot with full hook ups. I have propane, checked all fuses, unplugged the shore power and tried with just the 12V. Nothing. No fan or ignition clicking. Everthing else works.

It was 38 degrees last night, lol.

Any suggestions for a quick fix?
Click to expand...
i have an 05 and the thermostat contact doesn't close sometimes . i've had to just pull the cover and tap on the spring contact a couple times and that always seems to do the trick.
Ya might try that as its free
 
Trace the electrical wiring and push & wiggle all connections.

We never had that problem with our 2008 189FBR Fun Finder, but our new Grand Design (which has MANY problems) had this exact thing happen. The furnace randomly stopped working. Turns out it was an electrical connection that had just gotten out of alignment. After pushing the connections in, and wiggling it, the furnace has worked perfectly for many many cold nights here in Texas (-1 F at one point)

Just happens with travel.

Hope this works for you.

Liz

(still have/use/love our Fun Finder!!!)
 
By the way, you can use a regular house thermostat for the furnace. I replaced the one in our 2008 189FBR years ago. We don't use the furnace often, but it works great when we do!

(Also ran a light switch for the water heater electric element and mounted it by the other switches. Now I don't have to go outside to turn the electric water heater on/off. No more accidentally burnt out elements!! yes, I could have bought a matching switch, but I'm .... frugal)

Liz
 
1kotonk. I can attest to the fact, there are NO fish in Silverwood lake. I used to live in Southern California and fished (?) Silverwood many times at at different times of the year and at many different locations on the lake (yes, even at the dam) The fish you see in the pictures are plants brought in from other lakes for a photo op. LOL.
I don't know why this happened but, one time, back in the late 80's, we pulled our little 14' Playmore trailer there to camp for a few days with the kids. For some reason, we got so bored we left the same day !! That's never happened beforee or since!
 
You have probably already checked this but do you have enough propane. My furnace will not do anything if the propane gets to low, the stove burners will still work but not the furnace.
 
Furnace will not stay lit

Ok.. So my furnace fan comes on, the burner comers on and then goes off. It keeps trying and will come on but immediately goes off. Any ideas? Thanks for your help!
 
I got lucky, it was a simple thermostat replacement. Two wires and mounted the new thermostat works like a champ but now I can set a specific temp for it to come on and off. its not like I use the furnace a lot but I needed it the other night and it didn't work.

I posted a link earlier in this thread to the one I used, super simple and easy to install and use.

Jimbo, I believe you'll like the thermostat and easy install.

PaintyLiz, yep, the one I used was for a heat only home install.

Mjpguy, you may be right. I fished two days used lug worm, worm, anchovy, chicken liver, power bait and tossed lures. I spoke to every person who was fishing, nothing.
But it was good getting out in the sun and pulling the trailer out. Prado lake was my go to spot yrs ago but since they drudged the lake they have been having problems with algae.

Mitch, I thought of that and checked my tanks they were low and it was 38 degrees, but my water heater, range and frig worked. It turned out to be the Thermostat.

CRay, go on U tube and look up sail switch or RV furnace, there are a lot of videos I am sure you'll find something. If I remember correctly the sail switch activates the burners.
The fan comes on for a few seconds to clear unburnt gas and then the burners activate I saw a video where the sail switch was clogged with dog hair and would not let the burners burn.

Good luck..
 
01.jpg

03.jpg

Photo 1 is the new thermostat mounted and the old one removed. The second photo is the old thermostat with the cover removed. The control lever that turns the furnace off and on has a little triangle on the lever. That triangle separates the contacts when in the off position all the way to the left. When you push the lever to the right the triangle also moves and allows the circuit to contact and turns on the furnace. I believe the circuit contacts were dirty and if I would have cleaned them it would have allowed my furnace to turn on. I didn't bother trying to mess with it because I already had the new thermostat and just hooked it up.

something to think about.
 
Glad you now have a working thermostat and perhaps one which is more reliable. Oxides on copper are non-conductive and form quickly. When you connect to a copper wire or contact you must break through the thin copper oxide to make good contact. I surmise that the contact in the original thermostat did not have enough pressure to be 'gas tight' and therefore an oxide formed on the copper.

Thanks for educating us that at least some home-type thermostats can be used in our trailers.
 
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