Forum Discussion

silvercorvette's avatar
silvercorvette
Explorer
Jun 29, 2013

efficiency of the heater/furnace

I haven't had this experience with the camper I am using now (the 2009 H/R may have a different type furnace than the 20006 Jayco but I doubt it) but last year it was cold outside and I was at a campsite. The dogs told me they had to go out side to poop (yes they have a way of letting me know they need to go out) since it was cold outside I hooked them both up instead of taking them out one at a time that way I would not have to only stand outside 1/2 as long. I did not have much in the way of warm clothing because I expected to be home before this unexpected cold snap. The RV furnace was running and I could feel the nice heat fro the exhaust warming me up as I stood outside.

But this made me wonder how efficient the furnace is, all that wonderful heat pouring out of the RV keeping me warm was wasted heat.

I have read about RVs designed for cold weather use that have better insulation and thermopane windows but what about furnaces? I would think that with all the improvements in home furnace technology there must be a way to design an RV furnace that does not waste all that heat by dumping it outside.

I have noticed that when I used the oven or stove the RV gets hot inside and the A/C has to work hard to keep things comfortable obviously all the heat from the oven and stove is remaining inside the camper.

Are there options for more efficient heat exchangers? MY RV is a 2009 are the newer ones more efficient?
Seeking Advice

7 Replies

  • skipnchar's avatar
    skipnchar
    Explorer
    Jun 29, 2013
    It's a kind of REGULAR idea on the forums where someone suggests capturing all that "wasted heat" and put it back inside the RV. If anyone actually DOES that we probably won't be hearing from them again because THAT'S where all the CO gas goes when the furnace is running. Most ANY safe furnace will combust using outside air (so the furnace does not exphixiate anyone by burning air they need to breath) and it doesn't POISON anyone by putting CO into the living quarters. They use a neat exchanger system and yes it DOES vent some heat. To have an EFFICIENT system you would need a far LARGER exchanger and that is money, weight, and space. ALL of those things are not available in most RVs.
  • silvercorvette's avatar
    silvercorvette
    Explorer
    Jun 29, 2013
    Thanks for the replies. When I stand outside and feel all that heat pouring out it bothers me. I don't do very much cold weather camping but if I was every in a situation where there would be a problem finding a propane filling station I would pull in the slides to have less area to heat. I also have a front and rear A/Cs and the heat ducts are part of the A/C system (similar to a 2 zone heating system in a home) so if I run the front furnace I'll only be heating the bedroom.

    If I am hooked up at a C/G I can use the Electricity to run the A/Cs heat pump, I am concerned with being in a situation where I am boon docking in an area where there is no place to refill my tanks.

    Not only is running out a concern but I am paying $26 for a 30 pound fill up at BJs in LI and that has been lasting about 7 days. If I do not run the furnace it would probably last a month. Right now I am running the fridge and water heater on propane because the circuit breaker in the house I am plugged into keeps popping if I try to run too much stuff on electricity.
  • Chris_Bryant's avatar
    Chris_Bryant
    Explorer II
    Jun 29, 2013
    It's really more about the space- to be efficient you need to extract more heat, which takes a *much* larger heat exchanger.
  • aruba5er's avatar
    aruba5er
    Explorer
    Jun 29, 2013
    Why make anything efficient when propane WAS 10 cents a gallon? Retooling and engineering costs money. Would people pay for that. Keep on making the same stuff. No options. they have to buy our stuff. Thats the way the manufacteurs think. Attwood makes a two stage furnace. Nobody buys them because of cost. I would, IF the present furnace ever dies but by then.it"ll be time to replace the camper too and back to the same new junk we had before. Remember it's all about the money.
  • beemerphile1's avatar
    beemerphile1
    Explorer
    Jun 29, 2013
    RV furnaces are very inefficient and to my knowledge none of the regulation affecting home units apply to RVs.

    It is easy to calculate the efficiency of any furnace. Look at the data plate and compare the input BTU and the output BTU.
  • silvercorvette's avatar
    silvercorvette
    Explorer
    Jun 29, 2013
    Dutch_12078 wrote:
    You didn't say what make/model your furnace is, but the quote below applies to the Atwood/hydro-flame 8500 series furnaces used in many RV's.

    NOTE: Furnace efficiency rating is a thermal rating determined under continuous operating conditions, independent of any installation. Efficiency rate is given at 77% minimum, actual efficiency rating may be higher.

    Atwood 8500-IV Series Furnace


    I am not sure what furnace I have, when the rain stops I'll go outside and see if I can find the manufactures name, 77% seems pretty good maybe all that hot air pouring out of the exhaust is a small percent of what is being delivered to the interior.
  • Dutch_12078's avatar
    Dutch_12078
    Explorer III
    Jun 29, 2013
    You didn't say what make/model your furnace is, but the quote below applies to the Atwood/hydro-flame 8500 series furnaces used in many RV's.

    NOTE: Furnace efficiency rating is a thermal rating determined under continuous operating conditions, independent of any installation. Efficiency rate is given at 77% minimum, actual efficiency rating may be higher.

    Atwood 8500-IV Series Furnace

About RV Tips & Tricks

Looking for advice before your next adventure? Look no further.25,151 PostsLatest Activity: Jul 25, 2025