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furnace not working!
Yahoo Message Number: 108895
Hi Folks

Here I am in Rio Grand Valley of TX, having very cold weather:-( My furnace has stopped working. One day it did; next day it didn't. I know that the thing needs to be pushed right over to the far right but nothing happens. I have 1/2 tank propane. House battery indicator reads full charge.

Any thoughts on why & how best to get it out?
 I'm in an '03 26'MB. If I take the drawer above out, will that help access it?
 I have an RV guy coming this am but would like to do what I can to expedite the solution.

thanks, Pat
Re: furnace not working!
Reply #1 –
Yahoo Message Number: 108897
Quote
My furnace has stopped working. One day it did; next day it didn't. I know that the thing needs to be pushed right over to the far right but nothing
Pat, I had the same symptom you described in our 2002MB.  After moving the thermostat back and forth several times the furnace fired up.  I "assumed" that the thermostat contacts may have been at fault.

Let us know what the RV tech discovers.

Good Luck, Malcolm In Chilly Austin
2002 Mid Bath
Re: furnace not working!
Reply #4 –
Yahoo Message Number: 108907
Quote
Here I am in Rio Grand Valley of TX, having very cold weather:-( My furnace has stopped working. One day it did; next day it didn't. I know that the thing needs to be pushed right over to the far right but nothing happens. I have 1/2 tank propane. House battery indicator reads full charge.

Any thoughts on why & how best to get it out?
 I'm in an '03 26'MB. If I take the drawer above out, will that help access it?

thanks, Pat
Hi Pat,
 We have a 2003 Midbath as well. A few times it seemed our furnace would not turn on. We discovered that after moving the thermostat up and tapping it a few times (by hand not with a hammer), it would start up. I think the contact points on the thermostat were stuck.
(I'm going with a digital thermostat next year.)

Did you also check your fuses?

Good luck!

Steve K.
Steve K

2003 Mid-bath
Re: furnace not working!
Reply #5 –
Yahoo Message Number: 108909
This is probably too late to help, but for future reference... it's fairly common for the thermostat's contacts to oxidize, especially between heating seasons when it's not in use. It's easy to diagnose this.
 If the furnace won't start even with the thermostat turned all the way up, take off the plastic cover. You'll see a red wire and a white wire going to two screws on the left side of the case.
 Using a straightened-out paperclip or a short piece of wire, bridge those two screw terminals together. The furnace should start immediately. If it does, you know you have a thermostat problem. Usually, moving the lever back and forth a dozen times or so will clean off the contacts and cure the problem.
 On the other hand, if the furnace *doesn't* start when you bridge the thermostat's screw terminals, then you have a furnace problem.
 One other troubleshooting tip to keep in mind: if the furnace starts and the blower runs, but only cold air comes out, there are three possible causes. The most obvious is that you're out of propane. The second is that propane isn't igniting, due either to a failed board or crud/spiderwebs in the burner area.
 The third possibility is one that most people don't know about. In the furnace's air duct there is a "sail switch"--a movable paddle--that controls the burner's gas valve and ignition circuit. If the burner were allowed to run when the blower wasn't moving air, the furnace would soon overheat, and could cause a fire. The sail switch prevents this by only turning on the gas after its paddle has been blown aside by moving air.
 But if your house batteries are low, so the blower isn't blowing fast enough, the sail switch  won't be sufficiently deflected by the airflow, and the burner *will never light.* (This can also happen if the sail switch is stuck due to rust or cobwebs.) It's happened to me.
 I know you checked your house battery voltage, Pat, so this doesn't apply to you. But I mention it to make others aware of the potential problem. If the blower's running, after all, you probably wouldn't suspect low batteries as the reason you're only getting cold air. But it's something to watch out for.

Andy Baird http://www.andybaird.com/travels/
Andy Baird
2021 Ford Ranger towing 2019 Airstream 19CB
Previously: 1985 LD Twin/King "Gertie"; 2003 LD Midbath "Skylark"
Re: furnace not working!
Reply #6 –
Yahoo Message Number: 108910
Well, the furnace is out all over the floor, the RV guy has gone for lunch however just before leaving, he put both new motherboard & new thermostat
Re: furnace not working!
Reply #7 –
Yahoo Message Number: 108912
One small point that I didn't see mentioned about the thermostat contacts:  To clean the contacts just put a piece of paper (not sandpaper) between the contacts and move it through a couple of times.  That should clean the contacts and renew the connection.  JB
Re: furnace not working!
Reply #8 –
Yahoo Message Number: 108916
Pat, I would think that the possibility of both the board and the thermostat going out at the same time would be slim to none and slim left town this morning. I think someone is taking advantage of your plight.  My limiting/sail switch went out on mine about a year ago and the repair guy wanted to replace both the circuit board and the stitch.  Of course the switch is much cheaper than the board, but I wanted proof that both were bad, which of course he could not do. Trust but verify.

Larry
2001 MB
* Not to be confused with Larry W (3000 of my posts are actually from expert Larry W due to Yahoo transition mis-step)
Re: furnace not working!
Reply #9 –
Yahoo Message Number: 108925
Quote
Pat, I would think that the possibility of both the board and the thermostat going out at the same time would be slim to none and slim left town this morning. I think someone is taking advantage of your plight.
=========================================================== I agree with Larry.  Atleast save the old parts. One or the other might just be good.
Dave
2004 PleasureWay TD