Electric Heater warming/Airstream Furnace Circulating

[Alice&Billis]

It dipping down into the upper 20's tonight in East Texas and I've been waiting for this weather to try my experiment. Help me if you can!

Here's the set up: I'm in my 2006 Safari, and I've shut the gas off to the furnace and have it running to circulate the warm air produced by the electric space heater I'm paying for at the campground. Obviously, the furnace continues to attempt to detect gas or heat for about 2 minutes and then shuts down regardless of the temp selected on the thermostat. It won't come back on unless I dial up another degree of temperature. I thought (guess I'm crazy) I had read these postings before where someone let their electric heater recirculate the warm air throughout the coach, including storage, tanks, floor.

While I'm at it, is there anyone out there with a stock electric and gas combo furnace in their Airstream coach?

Thanks,

Bill Hoot/Tyler Texas

[Kevin245]

We use a 1,500 watt ceramic heater and a small fan (10") to circulate the air. It's comfortable for us down in to the mid 20's. A few weeks ago we were in the in 15 degree range...it was a little on the nippy side at that temperature.

[SteveH]

We don't get quite so cold down here, but when there is a freeze expected, I leave an electric space heater on and keep the cabinet doors open. It has worked OK so far.

However I did blow all the lines with compressed air yesterday.

[bryanl]

You must have one of those modern smart furnace controllers! The old ones did not shut the fan off when the thermostat called for heat and you were out of gas - that meant not only a cold morning but a cold morning with a dead battery. Yours is one of the battery saving types, it sounds like.

I would not worry about freezing inside until the average of the daily max and min gets below freezing. I've had it go below 20F here with highs near 50 and not suffer freezing damage.

Use a space heater with a fan positioned so it can blow air down the length of the trailer. I have one connected through a water trough anti-freeze plug (found at HomeDespot) that turns on the 800 watt setting when temperatures get below 40F.

I'd also not worry about freezing the holding tanks. If they are empty, or nearly so, they won't suffer. If they are full, empty them. It takes an awful lot of cold to freeze tens of gallons of stuff.

[silverback]

We used our Lasko ceramic (model 751320) 1500 watt heater last week in low 30 degree weather and it kept the trailer comfy. I started with the lowest setting (60 degrees) at night but that resulted in 3 large cats sharing the bed with us. Setting it at 65 -70 was optimal. We did trip a breaker one morning when we were using the toaster, heater, coffee maker and convection/Microwave at the same time.

-KL

[pmclemore]

Bill,

It sounds as if you have your furnace set to run as if it had gas. Don't you have a fan-only setting you could use?

Pat

[doorgunner]

Alice & Billis;

IF you are NOT pumping propane to your heater---you might want to block off the intake and exhaust ports that go directly thru the side of your trailer. This is a direct connection to outside cold air. Get it -- draft city!!
I just stuff a shop rag between the dauber screen and the ports. stops the cold air.
just REMEMBER to open the ports when you turn on the propane!!
Be Smart

I realize this may not be helping with directing air toward your plumbing BUT anything you can do to make your heating more efficient will increase inside temps and therefore make more heat available to pump into your bellypan.

If you really get motivated you could install some 5" muffin computer fans in your duct work. they work on 12 volts.

[Airstream25]

Hi Bill,
Curious how everyone misses your point and makes off topic replies.

I don't know how to do exactly what you are asking but wonder if you placed the electric space heater directly in front of one of the furnace heating ducts, perhaps the force of the space heater fan would circulate some warm air through them including the tanks below deck. Maybe you could make an aluminum foil cowl around the space heater to direct more of the air flow into the furnace heating duct. The effectiveness of this could be tested by seeing if any air flow comes out any of the other ducts.

This of course has the risk of the space heater overheating something.

Originally Posted by Alice&Billis

Here's the set up: I'm in my 2006 Safari, and I've shut the gas off to the furnace and have it running to circulate the warm air produced by the electric space heater I'm paying for at the campground. Obviously, the furnace continues to attempt to detect gas or heat for about 2 minutes and then shuts down regardless of the temp selected on the thermostat. It won't come back on unless I dial up another degree of temperature. I thought (guess I'm crazy) I had read these postings before where someone let their electric heater recirculate the warm air throughout the coach, including storage, tanks, floor.

Bill Hoot/Tyler Texas

[Mike Leary]

The oil-filled radiators work best for us; one forward & other rear, never blown a breaker.

[Alice&Billis]

Originally Posted by pmclemore

Bill,

It sounds as if you have your furnace set to run as if it had gas. Don't you have a fan-only setting you could use?

Pat

My fan only setting kicks on the roof air blower only, which is not what I need. This may not be possible on my model, but thanks for the idea.

[Alice&Billis]

I guess I'm just lucky that way, being modern!!!!!!!!!!!! Guess I need to find out if there is some way to bypass the safety feature, otherwise I'll just go ahead and burn the propane. Thanks to everyone who has responded.

[dmac]

I understand what you are aiming for... as sounds like something I would do! It should work, but I'd be concerned about the electric ignition for the furnace retrying so often. I think that eventually the electrodes may burn up. There must be a way to jumper the furnace fan "on"... check the owners or installation manual.

[bryanl]

Guess I need to find out if there is some way to bypass the safety feature

Safety Feature? you mean the battery saving feature?

From some saying nobody is reading the OP and how this discussion is wondering around, I wonder if I understand what you are planning to do.

My reading is that you have a trailer with ye olde standard DSI propane furnace. You want it to blow air to keep the underfloor tanks and plumbing ventilated with warm air created by an electric heater in the trailer.

If that reading is right, the first impression is that it isn't worth hassling as the below floor stuff isn't particularly vulnerable to cold, especially if the tanks are empty or near so.

But, if you do want the blower to run, anyway, all you need to do is to rig up a switch to feed the blower directly from the 12v rather than through the controller board. You might be able to do that via the wiring access port on the side of the furnace.

If you wanted to get fancy, use a timer to turn on a relay instead of a switch. That way you could turn the blower on for, say, 10 minutes, every hour or two. Maybe build a little 555 timer circuit with relay, even. You will need to pay attention to keeping your battery charged if you do this, though. - it also sounds like a good way to fry the blower motor (I have had more trouble with motor bearings than any other furnace part).

[HowieE]

Liepper's idea is the way to go.

You can wire the fan motor directly but the idea of timing the fan is well worth considering for several reasons. The life of the fan motor, the noise level in the trailer, and the draw on the batteries, and battery life, even if you are plugged into the shore.

If you are not in a position to design a 12 volt timer circuit and are plugged into the shore consider using a 120 timer that has separate secondary contacts and wire the 12 volt fan circuit across the contacts of the timer.

If you do this don't cut the original fan wire but rather wire the timer from a 12 source in parallel with the original wire so as to retain the original functions when the timer is not in use.