Furnace problem in MH

[djohn]

I have a 2003 Mountain Aire W-22 that has a problem with the Suburban furnace. Occasionally, it will fail to light, usually in the middle of the night. It will blow cold air and most of the time it will relight after turning the unit off an back on. Sometimes this doesn't work and it gets real cold. I'm still under warranty and have had it in at the dealer where they cannot find any problem. I can't believe I'm the only owner experiencing this problem. Any ideas???

[djohn]

I have a 2003 Mountain Aire W-22 that has a problem with the Suburban furnace. Occasionally, it will fail to light, usually in the middle of the night. It will blow cold air and most of the time it will relight after turning the unit off an back on. Sometimes this doesn't work and it gets real cold. I'm still under warranty and have had it in at the dealer where they cannot find any problem. I can't believe I'm the only owner experiencing this problem. Any ideas???

[AL]

Hi djohn,

IMHO since it is still under warranty, I would tell them if they can't find the problem & fix it!! Then they should just put in a new furnace!! Good luck hope you solve this problem one way or another soon!!

[Cruzer]

Other than a mechanical issue with your furnace (which the dealer will take care of under warranty) there is another possibility.

If you run the coach into the middle of the night without any shore power it's possible that the battery voltage may be lower, which in turn will reduce the speed of the blower fan. If the blower fan is not turning at full speed it may not create enough air flow to engage the sail switch. The sail switch senses air flow and is designed to shut off the burner if something goes wrong with the blower in order to prevent overheating the burner assembly. It is possible that low voltage isn't giving the fan enough RPM to keep the sail switch engaged. Or maybe, the switch is sticking enough that it is prematurely tripping with less air flow. Of course, if you are plugged into shore power your batteries (and fan speed) should be just fine so this isn't a possibility. In that case I'd just head to the dealer. That's the big plus with Newmar - that 3 year warranty.

....If you have a thermocouple-try tightening the nut on the housing of the brain box....geof kaye

[Fred Ray]

One mor thing to have the dealer check is the lp pressure... The regulator may be bad. Had a friend that had the same problem..
Good Luck

Fred

[Kirk]

I would bet you that Cruzer has it right. Low battery voltage is the most common cause of the problem you have. And by the time you drive to the dealer to have it checked, the battery is charged back up again. If you want to test that theory, next time that it happens, start the chassis engine and then restart the furnace once the engine has run for a few minutes. If the furnace works, you just found the answer. A furnace will run a single battery down in less than one night if it is cold enough that it runs frequently.