Atwood? Furnace stopped during cold night...

[RCCFleetwood]

Hi everyone,

We took our RV out last weekend for the first summer trip of 2017. All was good, except for Saturday night, when it got down to the high 40's or low 50's and our RV heater was running quite a lot.

It ran fine from early evening until sometime in the middle of the night, I'd guess 3 or 4 am, and I noticed it was getting cold towards morning.

Got up in the morning and the heater appeared to be "on" still (green light on electronic climate control panel), but the heater would not run.

I turned it off (on the climate control panel) for about 5 minutes, moved the thermostat slider up and down, reset it around 70 degrees, turned on the heat and the furnace started up again, and ran fine into the morning hours, when I shut off the heat.

It seems that this MAY have happened once when I was testing it, but I thought I may have hit something while I was cleaning it out. I remember a "reset" button on the furnace outside, which I hit that day, went back inside, turned it back on, and it ran, so I dismissed it as something I did.

Any ideas what might make it do this? Something overheating and tripping a breaker?

Picture of furnace that looks similar to mine on the outside is attached. I'll get the exact model number in the morning when I can take the outside cover off.

Thanks very much.

[Skip426]

Don't know how much help this site would be for an intermittent problem , but reading through may give you some ideas.
There is an over heat sensor that if it stuck would prevent re-firing, but you'd have to get to it , to test when the furnace isn't working.

Troubleshooting RV Furnace Problems

[BFlinn181]

Skip is right, the 'reset' button might be the overheat thermistor. You need to check gas pressure and make sure no vents from the furnace are blocked or closed. If you Google your furnace make and model # followed by the word, "manual" you'll find owner's and service guides that can run you through the steps to check.

[RCCFleetwood]

Originally Posted by Skip426

Don't know how much help this site would be for an intermittent problem , but reading through may give you some ideas.
There is an over heat sensor that if it stuck would prevent re-firing, but you'd have to get to it , to test when the furnace isn't working.

Troubleshooting RV Furnace Problems

Originally Posted by BFlinn181

Skip is right, the 'reset' button might be the overheat thermistor. You need to check gas pressure and make sure no vents from the furnace are blocked or closed. If you Google your furnace make and model # followed by the word, "manual" you'll find owner's and service guides that can run you through the steps to check.

Thanks. I'll read that over, and look for the manual, see if there is anything in that to check it.

[mojoracing]

Mine did the sam thing and eventually got worse. It would start up and run fine but sometime during the night would try to fire tree times and then lock itself out. Mine has an led on the main circuit board that will flash trouble codes. Looking at the pic, yours does too. There is a sticker on the furnace that tells you what the different codes are. Mine turned out to be a sail switch.

[RCCFleetwood]

Originally Posted by mojoracing

Mine did the sam thing and eventually got worse. It would start up and run fine but sometime during the night would try to fire tree times and then lock itself out. Mine has an led on the main circuit board that will flash trouble codes. Looking at the pic, yours does too. There is a sticker on the furnace that tells you what the different codes are. Mine turned out to be a sail switch.

Thanks. I've been trying to get it to fail, ran it the other night, but it was fine in the morning (I did not sleep in it, was at home, and it was not quite as cold, but close)... If it fails again, I'll go out and remove the cover and check the LED. I'm hoping it won't fail again, unless it's at home... hahaha

We're going away for a couple nights again soon, so we'll see what happens.

[Al n Cindy]

One of the most common problems is oxidation on the terminals on the circuit board - 1 plug & 3 other wires to it. Caused me numerous intermittent shut-downs.

Plug/unplug all of them several times to clean. Scrape clean the male terminals on the circuit board - fine sandpaper or a knife will do it. I also spray them with terminal contact cleaner.


All of that said, I eventually had to replace the circuit board (buy a Dinosaur board - better made and will last much longer). Do you have only one heater? I have two and confirmed the circuit board needed replacing by switching the two. But this doesn't seem to be your issue...yet.

All of the above presumes you don't hear the igniter clicking when you turn on the heat. If you do hear it (stand near by while someone turns on the heat), then the issue may be on the LP side of things. First thing then would be to check for blockage of the orifice.

Good luck!

[RCCFleetwood]

Originally Posted by Al n Cindy

One of the most common problems is oxidation on the terminals on the circuit board - 1 plug & 3 other wires to it. Caused me numerous intermittent shut-downs.

Plug/unplug all of them several times to clean. Scrape clean the male terminals on the circuit board - fine sandpaper or a knife will do it. I also spray them with terminal contact cleaner.
Attachment 163192

All of that said, I eventually had to replace the circuit board (buy a Dinosaur board - better made and will last much longer). Do you have only one heater? I have two and confirmed the circuit board needed replacing by switching the two. But this doesn't seem to be your issue...yet.

All of the above presumes you don't hear the igniter clicking when you turn on the heat. If you do hear it (stand near by while someone turns on the heat), then the issue may be on the LP side of things. First thing then would be to check for blockage of the orifice.

Good luck!

Thanks. I've done just that... first thing I did, and I then ran the heat overnight one night while parked at home, and (though it did not get below 55 or so that night), it ran fine all night, was 70 degrees in there in the am, and the exhaust was slightly warm when I went out in the morning, so I know it ran all night. So MAYBE I've already fixed it, but won't know until the next night that gets down below 50... maybe not even this year!

BTW, I could not hear the clicking, but I'm not 100% sure I CAN hear it from inside, while moving the thermostat up/down, either.

[mojoracing]

Easy way to confirm the sail switch as they can sometimes read fine on a meter and seem to work fine when manually manipulated. Next time the furnace tries to fire and ends up locked out, try to gain access to the top of your furnace inside the coach. In my case, it was as simple as removing a kitchen drawer. Next, turn thermostat off and wait 15 seconds then switch it back on to the heat position. While the furnace is trying to start, bang on the top of the furnace. In my case it was enough to get the sail switch to move and the furnace to fire. If nothing else, it may get you a comfortable nights sleep in a pinch as opposed to freezing your baggets off. If it fires, replace the switch, in my case cleaning did no good. By the way, the bad switch tested fine.

[RCCFleetwood]

Originally Posted by mojoracing

Easy way to confirm the sail switch as they can sometimes read fine on a meter and seem to work fine when manually manipulated. Next time the furnace tries to fire and ends up locked out, try to gain access to the top of your furnace inside the coach. In my case, it was as simple as removing a kitchen drawer. Next, turn thermostat off and wait 15 seconds then switch it back on to the heat position. While the furnace is trying to start, bang on the top of the furnace. In my case it was enough to get the sail switch to move and the furnace to fire. If nothing else, it may get you a comfortable nights sleep in a pinch as opposed to freezing your baggets off. If it fires, replace the switch, in my case cleaning did no good. By the way, the bad switch tested fine.

Thanks. I suspect it might be the sail switch, as it acted just like you described here. I turned off the furnace then back on, maybe did that a few times, and had walked down the hall, maybe jarred it loose, and it started again.