Propane heat does not work - HELP !!!!

[girlie]

We have had it repaired over the last two weeks twice. New Thermostat, New circuit Board. Still it goes on for a while then shuts down and won't come back on. It's our propane heat not the heat pump. Any ideas!!!!

[skipwil]

A BIG welcome from East Tn.
I have NO knowledge on Furnaces. Other mechanical things some. Better to admit it than than being proved wrong.
You will find an awful lot of information here on The Forum.
Don't be afraid to ask questions-someone has "been there - done that"
that will hopefully point you in the right direction.
Again WELCOME...
Safe journeys...

[TXiceman]

girlie, are you running from 120 volt AC power of 12 VDC from the batteries? Measure the voltage at the 12 volt terminals in the heater when operating.

It could be a low 12 volt power or possibly a high temp shutdown requiring a restart to clear it.

Make sure all of the heat vents are wide open and not blocked as well.

Ken

[nbounder]

As mentioned, put your DVM across the 12V at the furnace (neg to the metal frame of the furnace, pos to (usually) the red wire near the control board. take a reading before turning it on, then start it and take another reading. That'll be a start in troubleshooting. let us know what you find.

[DAN L]

Originally Posted by girlie

We have had it repaired over the last two weeks twice. New Thermostat, New circuit Board. Still it goes on for a while then shuts down and won't come back on. It's our propane heat not the heat pump. Any ideas!!!!

what kinda furnace? these references should keep you reading for a while. have fun.

http://bryantrv.com/docs2/docs/hflamefurn04.pdf

Marksrv.com rv furnace troubleshooting

Marksrv.com Suburban RV furnace parts

RV Furnace Troubles - Fixing RV Frunace Problems

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

http://www.gmceast.com/technical/Nic...an_Furnace.pdf

[RV Wizard]

Hello Andi and William. . We are glad to have you join us here and we look forward to reading of your adventures and experiences. I am sure you will enjoy the website and forums. Good luck, stay safe and keep us posted.
If you find that the voltage at the furnace is at least 12.5vdc while operating, you have other problems. If it is low voltage, correct this issue first.
We really need more specifics as to what you are doing to get the unit back up and running. Are you simply turning it off and then back on or are you having to take it in for repairs. Has the unit be pulled out and cleaned lately? It should be done as a first step in repairing any problem. Debris, rusty burner, loose wiring connections, carbon on igniter electrode, partially restricted burner orifice, wrong lp gas pressure can cause erratic or no operation. Which thermostat was replaced. If it has a high limit thermostat, then you have air flow issues that need to be addressed. It could be on the return or discharge side of the furnace. Make sure no vents are closed. Look for kinked or crushed ducts.
Winnebago will usually provide the installation manual for the furnace. If you do not have it, one can be downloaded from the furnace manufacturer. Compare this to the actual installation. Verify the correct number and size of return and discharge venting ducts. I have ran into some units not installed properly causing the units to shut down on an over temperature condition.
The more information you can give us the better we can help you find the culprit.
Did the service center provide you with the old board? Why did they replace it and with what did they replace it with.

[girlie]

Wow - Thanks for all the information. We went to the dealer and first they checked the wiring and thought it might be loose wires however after repairing that the furnace worked for a bit and then stopped again. We went back and they tested everything and decided to put a new thermostat and circuit board in. The thermostat was a little loose. The unit began working. We found that it worked into the night the other night while we were on the road. We had it set at 72 and it ran then set it at 68 to go to bed and some time in the middle of the night it went off and never came back on. So yesterday we left it on ALL day while driving from FL to VA on 72 and it came on and off many times and kept temp at 72. I am about to go out and check to see if it stayed on ALL night. I think the mechanic mentioned something about the only other thing it could or might be is that it gets hot and shuts off and then needs to be re-set. So my question is - if that is what's wrong - how do we re-set and after 2 years of working properly what would need to be repaired if that is the problem so what exactly needs to be repaired for it to re-set itself when in use. THANKS all of you again.

[girlie]

OOPs I forgot to say we had new house batteries installed as well so it shouldn't be a problem with the voltage.

OK so I went out this morning and the heat is not running and apparently went off in the middle of the night. We left it set at 70 last night as it is freezing here in Virginia. The thermostat says 49. We have space heaters for backup but it appears that the unit stops working in the middle of the night after we drop the thermostat down a few degrees. ???????? We have new house batteries, wiring has been checked, new thermostat, new circuit board in the furnace. Basically it's been re-built.

[TXiceman]

I am begging to suspect low air flow due to a restriction. Trace out the duct runs and make sure you are getting good flow at all of the heat registers. Let us know what you find.

Ken

[dsbike]

My parents Winnebago Journey had similiar problems & we finally got it fixed. The advise given above is excellent & from some that are RV technicians. I would definately heed thier advice. I would also suggest you go to my thread at http://www.irv2.com/forums/f54/my-pa...ing-81009.html and pay particular attention to post 17. I outlined what the techs at Tom Johnsons did to troubleshoot our malfuctioning furnace. Just to add my own credentials, I am a heavy aircraft mechanic with 30+ years experience on all types of vehicles. I have some knowledge of what I speak, however I am not a trained RV Tech. Hope you get this repaired soon, I know first hand how frustrating it can be.

[Seajay]

Without seeing your furnace I would guess you are operating on your ''high limit switch''. a furnace has two limit switches against the fire box. You have one that tells the furnace to come on and produce heat. When the thrmostat is satisfied it turns off the gas and and the furnace cools and turns off the fan. If that ''limit switch'' is not functioning properly your next safety is the ''high limit'' switch which prevents the furnace box from getting too hot while the fire is on. It will act just like a thermostat in that it will turn off the gas, the fire will go out, the box will cool and the air fan will stop running. the great problem is getting it to come back on when you want more heat.

If it were me. I would look at the ''HIGH LIMIT TEMP. SWITCH''. I bet a six pack I could diagnose your problem in fifteen minutes if I could see the furnace. I use to repair gas heaters and tend gas fired boilers for a living ..

God bless our troops....

[girlie]

I think the high limit switch was investigated at Lazy Days and not found to be defective. The tech (Erics RV in Virginia Beach - not the original tech who "fixed" it at Lazy Days) has looked at it and said it is a dead spot in the blower motor. When it goes off you can rotate the blower motor with your finger and it will go on. does that make sense to you. Thank you for your response!

[dsbike]

Yes that makes sense. If the motor stops at a point where it has no electrical contact when it receives a signal to turn on, the current flow will stop & the furnace will not start. It has been my experience that the fan or furnace motor (one in the same motor) must start before the gas will flow & the igniter will ignite therefore lighting the burner. I do not know the cost of a new motor, but before I bought a new motor I would have the tech open up the burner & check it out to make sure it is ok. I would hate to buy a motor then in a week or 2 find out the furnace it self needs to replaced also. Hopefully the motor is not to costly & it will fix the furnace.

["007"]

girlie, welcome to irv2.
Before replacing motor I would try some contact spray on brush commentator for cleaning and oil the motor shaft you may have rust binding a area on shaft that gets it stuck in that position.