Furnace problem

[rlwhit]

Will not stay on. In the past low propane was the cause. The hot water heat stays on and the range works.The fan comes on and than it lights off. Stays on for a few seconds and than goes out. Maybe a simple fix, but it has me confused for now.

Thanks for your help

Dick

[Irlpguy]

Since the range does not need 12V to operate and the hot water heater uses 12V only to operate the valves and you indicate the furnace goes out shortly after the fan comes on, this would indicate to me there may be a problem with the 12V system. The furnace fan uses a considerable amount of power.

If you are plugged into shore power then my guess may well be wrong, however if you are not, then I would check the battery condition.

[HamRad]

Dick,
Have you looked in the combustion chamber to see if an insect or spider has gotten in? Often times that is a problem. Hopefully Ozz will be by soon to give some proper advice. Good luck.

How's it going with the boat? Some pics would be nice. Keep enjoying. Dennis

[Ozz]

Hi Dick,
That is a classic sign of a dirty flame rod, or also as Dennis said, sometimes a blockage. See if you can get in there and clean that flame rod and inspect it, Some folks have blown out the insides with compressed air.
Good luck.
Ozz

[Ozz]

OH, it could also be a sail switch, or pressure switch. I think they just use sail switches, but don't know all the different style and makes of furnaces they might use on these different units.

[DQDick]

Atwood was at the Rally and one of the reasons I go to presentations I know everything about is that they continually prove that I don't know half of what I think I do Here's another thing they said to check especially if it's getting cold. How full is your propane tank? According to them, as the tank empties the amount of gas pressure it can provide lessens. The stove and the water heater need far less pressure than the furnace to operate and so if the tank your on is getting low it may be able to operate the other two and not the furnace. They put out a flyer that showed how much the furnace required and how much the tank could provide under various conditions of temperature and fullness.

[Drifty1]

Dick, did you go outside by the vent to feel the air flow coming out the exhaust vent. Is it cold all the time or is it cold then heats up when the burner starts to light. Mine did something like that and I found I had a bad electrode. This would also tell you if you did not enough air flow. Also my son in law had a problem with a bad converter as he did not have a full 12 volt going to the battery. Hope you get it up and running soon as it is getting cold......

[The Weekenders]

quote:Originally posted by Ozz

OH, it could also be a sail switch, or pressure switch. I think they just use sail switches, but don't know all the different style and makes of furnaces they might use on these different units.

Yep, my bet is the sail switch. I have gone through two of those buggers since I bought my Monty new in 2008. Easy to replace.

[rlwhit]

Got er done. The suggestion Ozz gave about blowing air worked. Hope it lasts the winter. Az winters are not that cold. Thanks everyone for your input.

Dick