furnace peculiar

[rriverstone]

Ok, at first, I thought it was just me. It's not; it's the furnace.

I noticed the red wire to the thermostat had been disconnected and the screw kept loosened. So, when I moved it here, I reconnected everything. Next morning, I came out here to find, even with the thermostat switched to "off," the damn furnace was running! I didn't feel any heat; I only felt cold air coming out the vents. At first, I thought, oh, hell! It used up all the propane! But I turned everything off, waited a few minutes and fired her up, getting warm air very soon.

So, I put it back the way it was before I "improved" it.

Fine.

A few times, I've noticed the temperature dropping to the creepy crawly point and have discovered the blower fan is simply circulating cold floor air up through the vents. I have a little ritual for this. I turn everything off, disconnect that red wire (which I only hook to the screw when I want the furnace to work) and unplug the 2 electical cables inside the furnace box (after the blower fan stops, which takes a few minutes).

I heat a cup of coffee, which takes 2 minutes, and, while I wait, I turn on the oven pilot, give it a minute to have some gas and light it, to make sure I still have propane and to "cheat" and get some warm air for a few minutes, before the carbon monoxide can kill me. Then, I go back to the furnace, reconnect everything, set the thermostat to about 55f and everything works as it should. So, I sit in front of the oven with the door open, my coffee cup and ashtray on it and mumble to the cat about the stinkin' furnace.

The best way to describe the problem is this: I think the thermostat "feels" the right temperature to signal the furnace. I think the furnace always receives the signal and starts the blower fan. I think, intermittently, whatever triggers the propane to light is asleep at the wheel. but I don't know what that is or what to do about it. I guess it's an electronic ignition; I see no pilot light or door or opening to light it with a match. Could it simply be a dirty contact?

I see no brand name or model number on the furnace, inside or out.

It's 12f right now, at 10pm. It's predicted to get to around -3 or 5 tonight. I have NO idea how much propane I'm burning up, and am keeping the thermostat down at 55f, to try to stretch it. Before I moved in, I bought 2 15 bottles and one um is it 25? bottle of propane. I have one of each hooked up and open right now.

I'm scared I'm going to freeze to death and kill all my animals, too, and am afraid to go to sleep.

[Acadianmom]

I think most of the furnaces in RV's are probably Suburbans. Over the years they have been the most aggravating thing to operate. They would run until I was baking, the heat would go off and it would only blow cold air and I could never get the heat to come back on. They have something called a sail switch that sticks. I just remember that from trying to have them repaired. I only use electric heat now. You might try looking on the RV.Net forum and do a search for furnaces. There is a lot of information but don't know if will help.

Martha

[avalen]

I agree with Acadianmom, sail switch,
heres a link on rv.net that discusses the issues of the sail switch.
http://www.rv.net/forum/index.cfm/fusea ... m#24647748

[rriverstone]

It's my own fault. I laid a rug on the living room floor. It covers a floor vent. It's under my bed; nobody walks there, except an occasional cat, on its way from bed to food or litter box.

I will fashion a small frame of 1x1 inch bits of wood with a piece of metal screen over it and slip it under the rug, screen side up, so air can pass more easily. I'll also drill holes in the wood.

I'll bet that solves it. Thanks.

The problem: From time to time we hear from folks who say "The blower comes on but the burner does not" often the problem is low air flow so the sail switch that senses air flow never closes.. Thus the burner never comes on.... Page 2

The theory: Blocking a vent increases the back pressure on the blower and thus reduces the air flow... Making it so the sail switch never closes.

The fact: If the furnace works.. You don't have the problem thus you don't need to worry about the theory.

Personal observation:

I have often blocked off a vent for one reason or another and never had a proble.. but if you block enough,,, Then the furnace simply will not heat.

[Bethers]

Yeah, very important to not block any vents. Hope that solves it. If not, sail switch - which mine needs right now - so I'm without my furnace working until I go get that replaced. Will do that when I leave where I am. Since I keep changing that date, haven't got it done yet. If I didn't have electric hook-ups would have to do so - but have little electric heaters working for me.

Hope uncovering that vent works for you - sail switch is not expensive in and of itself, but not always easy to get to -