Furnace while driving

[Chaplain Kent]

This is my first winter with my 1982 280 Turbo Diesel and we have found the heater to be anemic at best. We live in Wisconsin and planned on using the rig all winter. I have the tanks all set so they will not freeze but now my wife and I freeze as we drive. The heat strip on the AC blows cool air at its hottest setting and I can find no way to turn the engine heater up any more than it is. Here is my question. Can we run the furnace while we drive?

[87MH]

Originally Posted by Chaplain Kent

.....Can we run the furnace while we drive?

I would think that would be a safety issue - several of the RV's at Colaw's (RV Graveyard) appeared to be burnt - don't know if the fire started at the fridge, the water heater, or the furnace, though.

Are you sure there is not an auxilliary cabin heater hooked up to the engine cooling system? The aux cabin heater was "standard" on all of the 345's I have looked at.

You may want to look into the possibility of having one installed in your unit, if not presently equipped. They use a standard heater core with a squirrel cage fan.

Most all of the "automotive" catalogues have them listed.

Instead of the AC heat strips (don't know if you have 1 or 2), you may want to consider a couple of small 110 ceramic heaters (on separate circuits) if you are willing to run the gen set anyway. With extension cords you could position them around the cockpit where they would do some good.

[TomW]

Originally Posted by Chaplain Kent

...Can we run the furnace while we drive?

I have thought about this question a lot for a different reason. A while back, I read someone's account of needing to transport their new-to-them vintage Airstream trailer in the middle of a very cold winter. By the time they had reached their destination, three of their windows had broken for no apparent reason.

I wondered if the glass had frozen in place, and could not flex as they went down the road. Old window seals (like some of mine ) develop more surface area with time which could freeze tightly. In the off-hand chance that I should need to move my Overlander when it is extremely cold outside, it would be nice to know if I can run the furnace to keep everything thawed.

In my opinion, the furnace is the safest gas appliance to run simply bcause it has a sealed combustion chamber. The question is will it run properly while going down the road at 55 mph? Will the airflow somehow suck out the flame? I don't know.

There is a simple experiment I meant to try earlier this year, but just forgot to do: My furnace has a pilot light. I figure I can light the pilot (but leave the thermostat OFF), and make a run or two down the interstate. If the pilot light is still lit when I return home, that should mean the main burner would run fine also.

Comments?

Tom

[87MH]

Originally Posted by tcwilliams

.... I figure I can light the pilot (but leave the thermostat OFF), and make a run or two down the interstate. If the pilot light is still lit when I return home, that should mean the main burner would run fine also.
Comments?

Tom:

The following is based on intuition only - no facts to back it up...

I would be concerned about the airstream down the side of the camper at highway speed preventing the proper flow of hot exhaust gasses LEAVING the combustion chamber. This would result in an overtemp situation in the chamber, resulting in a possible burn through, ultimate fire, destruction, death, and the spewing of brim-stone and hell-fire.

IF there were a burn through of the combustion chamber, I don't know if there are sufficient safe guards to shut off the propane flow - that, plus - IF a high air pressure exists at the area of the combustion inlet, it would tend to increase (feed) the propane fire, and accelerate any fire IF the flame were to leave the combustion box.

If you HAD to have a "heater" in the interior - I would think a "radiant" (no visible flame) type of propane/butane heater would be much safer.

Just my thoughts - the advice is worth what you paid for it.

Not responsible for actual damages - yadda, yadda yadda...

[TomW]

Originally Posted by 87MH

...I would be concerned about the airstream preventing the proper flow of hot exhaust gasses LEAVING the combustion chamber...

Dennis,

At least on my furnace, in normal operation, the exhaust gases are blown out of the combustion chamber by a fan. Since the fresh air going to the combustion chamber is also coming from the outside, I can not see a problem with insufficient airflow in the combustion chamber. I was concerned about general turbulence disturbing the airflow.

And, thinking out loud, it seems that if spent gasses could not leave, then fresh air could not get in. In that case, the flame would either die, or not have enough energy to melt a hole in anthing.

I guess I was hoping a turbulent air flow dynamicist was lurking on the board today looking for another technical paper topic.

Thanks for the response; That was just the type of counterpoint I was looking for.

Tom

[3Ms75Argosy]

This last trip, I tried twice to tow my trailer with the pilot on - I figured I could easily fire up the furnace at stops to warm up. Both times my pilot had blown out.
Good luck!
Marc

[TomW]

Originally Posted by 3Ms75Argosy

This last trip, I tried twice to tow my trailer with the pilot on...Both times my pilot had blown out.

To me, that means it is a bad idea to try and run your furnace while on the road.

Sure, electronic ignition would be a slightly different case, but enough air to blow out the pilot is enough air to upset main burner operation.

Thanks Marc

Tom

[85/345]

I have a 2003 Duramax Diesel and it came with a bra, not sure that is what it is called, that goes on the front of the truck during the cold months. I think this helps the engine stay warm. I don't know if this also helps with the heat or not but it might be something to consider. You might need something on the front of your AS that doesn't allow so much cold air to hit the engine. Just a thought.

Thanks,
Brian

[john hd]

chaplain kent.

here is what the manufacturer of the furnace says:

http://www.rvcomfort.com/suburban/se..._questions.php

scroll down to question number 5

i like the idea of getting your engine coolant powered heater to work better. are there shut off valves installed in the heater hoses? are they open? are the aux. heater hoses in good shape? (they are not collapsed or kinked)

perhaps the heater core itself needs some attention, maybe a good back flushing is in order.

if all else fails, adding some sort of "bra" to the radiator may be a good idea.

keeping a diesel warm in wisconsin can sure be a challenge!

john

[87MH]

Originally Posted by Chaplain Kent

......I can find no way to turn the engine heater up any more than it is.

Two more things occured to me -

First, is it possible that a PO (Previous Owner) removed the thermostat from the engine? The thermostats on the 454's are set between 205 and 210 degrees. Your temp indicator should read at least 180 to 200 degrees.


Second, there should be an air dam covering the space from the bottom of the windshield to the top of the radiator - this is to direct all of the air flow through the radiator and around the engine. Behind the air dam are the flexible ducts that direct the heated (or cooled) air to the defrost and panel air vent openings. If one (or more) of these ducts are disconnected (or holed) any air getting behind the air dam will blow directly into the coach area.

[overlander63]

Originally Posted by john hd

if all else fails, adding some sort of "bra" to the radiator may be a good idea.

keeping a diesel warm in wisconsin can sure be a challenge!

john

Try duct-taping a piece of cardboard from an old corrugated box over the front of a portion of the radiator. Drive the coach and see:
1- if the heater works better
2- the engine doesn't overheat.
Just try not to cover more than about half the cores in the radiator.
If it helps, you are in business, if the engine runs too hot, cut a smaller piece of cardboard, and re-test.
I have used that solution on some school buses, to get enough hot water to the aux heater at the rear of the bus.
Terry

[Chaplain Kent]

Thanks for the many replies and most of all for the link to Sububan, which I bookmarked for furure resource. I discovered that the heat strip was not working and fixed it but even then it only works without the fan, is this correct? So we got a small heater to place next to my wife's feet for this weekend's trip to the WBCCI luncheon. We will not run the furnace until we set up camp for the night.
The engine temp is correct so I will investigate an aux. heater. I am also considering a curtain behind the driver's seat area to wall off that area so I am heating less space.
Thanks again and if anyone else has suggestions please keepthem coming.

[ALANSD]

My heat strip works with the fan. It gives enough heat to warm us overnight with the outside temps in the low 30's. Using it while driving it has heated the inside but we don't have the low temps you will.
What about an auxiliary electric heater running off the generator? Just a thought.

Also a thermostat question-- I believe my MH does not have one and have not actually looked ...but in the cooler weather the engine runs in the 125-150 range ( on the dash gauge) .... In warmer weather it runs 160-180, rarely higher. Should I put in a thermostat? Would ruinning hotter in the winter be better? I am not concerned about the heater, mine is bypassed anyway.

[74Argosy24MH]

Originally Posted by ALANSD

Also a thermostat question-- I believe my MH does not have one and have not actually looked

Doesn't sound like it running that cool. Cool running engines don't boil the moisture out of the oil; the fuel in the mixture isn't as fine so combustion isn't as complete and fast, cylinder wear is greater because there is more fuel on the walls. A thermostat also restricts water flow, this provides better heat transfer than when coolant rushes through the heads, radiator and around the cylinders.

John

[wascobob]

ALANSD...Assuming you are running a 454 big block in your MH,... I would agree with what John just said in the previous post, but would add the following:

BB pistons are cam ground (out of round while cold) and are round only when the reach full opperating temp. By not running with the proper thermostat you are creating more cylinder wear than necessary. Thats what the big boys tell me.

CHAPLIAN KENT... I used to run my refer,water heater, and furnace while on the road with my old 1975 Superior and never had a problem. Haven't tried the furnace part since I got our 1988 290 MH, but do run refer. and water heater on the road always. Probably not a good thing, but there are a lot of safety devices built in.

[TomW]

Originally Posted by TomW

...A while back, I read someone's account of needing to transport their new-to-them vintage Airstream trailer in the middle of a very cold winter. By the time they had reached their destination, three of their windows had broken for no apparent reason...

Seeing other threads popping up about winter towing revived my interest in locating that account. Here it is.

Tom

[Chaplain Kent]

Since my first post we have made several trips with the motorhome on very cold days. I have used a small space heater along with the generator when needed. Also I have worked on the cable which operates the heat adjustment and it now gives off adequate heat. However, this cable is not connected to the dash! I have it connected via coat hangar to the vent by the passenger compartment. Does any one know if this is a GM part?
Thanks
Kent

[dscluchfc]

Of course the manufacturer is going to advise against EVER towing with the furnace on. Their lawyers would be foolish to advise otherwise. And, some states do have laws against towing with propane on as they are concerned that in the event of an accident, a fractured line could result in a blowtorch.
However, that being said, I have friends that have towed for over 35 years with frige on in the summer, and both furnace and frige on in the winter, with no problems.
Would think this is an activity that you just have to decide at your own risk given your circumstances.
In winter, I would hate to be towing over a mountain pass where I KNEW it would be below freezing for very long, and have no heat in the trailer....can you say frozen lines?...like say from Artesia NM to Alamogordo NM where the mountain is over 9000 ft at Cloudcroft. The road might be clear, but the temp could be well below freezing on the mountain and well above freezing at Artesia and at Alamogordo.