That giant sucking sound

[MaxwellD]

Greetings again,
Well actually - it is SILENT as a thief in the night, but my 30 gal propane bottles only last 7-10 days. My 2018 3737 FL is parked at home, but I keep the furnace on for the occasional freezing periods. I am in Texas where it has been low 30’s / upper 20’a at night so I leave thermostat at 55 degrees.
I also noticed that the heater exhaust vent blows a lot of hot air to the outside - I guess it is supposed to do that, but that seems wasteful and inefficient. What’s up with that too?
Off to buy more propane now, thanks,
Max

[CADman_KS]

Is there a reason that you don't winterize? That would save a lot on propane.

If you're going thru one 30 lb bottle every 7-10 days, at those temps that doesn't sound out of the ordinary. While a unit can stay warm enough, it doesn't take very long for them to cool back down. The insulation, while there, isn't very thick...

[Ram Montana High Country]

If you're plugged into 50a at home, leave the fireplace on low. For as small as the furnace is an RV, it's hard to make them extremely efficient hence the hot exhaust, same with the gas side of hot water. I also use a free standing radiator style heater when in storage.

[MaxwellD]

Thank you. I dont winterize mainly bc we are prone to hook up and go somewhere for a long weekend at a moments notice. (Well that was true before hip replacement surgery in Dec so now I am grounded for a while!) Is all that hot air exhaust normal?

[MaxwellD]

Ok that sounds like a good plan - and cheaper. We rarely get extreme cold for days on end anyway!
Thanks

[DQDick]

Yes, the hot exhaust is normal. Since we winter in the high desert of NM we use a home 120gal propane tank. We disconnect the rig tanks where they feed the black pipe along the frame and hook the hose from the home tank there. Keeps us warm and avoids numerous trips to the propane dealer.

[MaxwellD]

Probably a bad idea to somehow capture that exhaust and put it back in the belly or basement due to CO ?

[Carl n Susan]

The propane furnace is only 40-50% efficient and that is why there is so much heat coming out the exhaust. Don't try to recycle the exhaust. The CO will get you.
A tank a week is pretty reasonable for you situation.

[sourdough]

Your propane usage seems in line to me. I've gone thru a 30gal tank in 3 days in extreme weather so your results sound about right. Sounds like you have a plan on using auxiliary heat in addition to the LP and that's a good idea to help with the usage.

[jsb5717]

We have an 80% efficient furnace in our house and the exhaust going out the roof is also hot...that's just the way furnaces work. Newer furnaces for home can be much more efficient now, though, and really reduces the heat loss. I don't know what it would take for the RV market to develop that kind of efficiency in their furnaces...or what it would cost.

[BobStack]

Get a small electric heater or use the fireplace to keep her from freezing. I would also recommend a wifi thermostat to inform you if the heat goes out.

[jeffba]

get a compressor and just blow it out

[Dave W]

You have to do a comparison on costs of each. The room heaters usually have at least a two position setting - 800/900 watts and 1500 and often a thermostat. If Texas power is reasonable, that might be a bconsideration. Tractor Supply (TSC) at the local store is currently is $3.09/gallon while at my locally owned RV guy that I try to give a some of my business it was 3.60/gallon yesterday when I had a tank filled. The local electric power is .14/kwh.



Do your Texas base arithmetic but also add in a factor for electrics convenience (gas/diesel and time). You also need to factor in that the propane furnace also provides some belly and water line heat in hidden places that an electric heater wont reach.


Now, capturing waste heat. We used waste heat from our large heavy duty gas turbines two ways - one as regenerative cycle to preheat combustion air and secondly, to heat water into steam (HRSG) to run steam turbines. Why not design a tube system that uses the waste heat from an RV furnace and returns some back to the furnace and some back to the coach interior. Hmmm. Yes, I know that it wouldn't be something that could be attached permanently, but use by a FTer or while the 5ers in storage at home might curtail a bunch of propane use.



(dang, too much free time on my hands with this epidemic along with winter blahs)

[Daryles]

Air gaps:
Look under your frame. There are lots of holes and gaps. This allows cold (or hot, summer time) air into your underbelly and can freeze your pipes.
Use gorilla tape to close off any small openings (hydraulic lines, slide cylinder).
Use aluminum sheeting and cut to fit around the hydraulic jacks. Leave the opening around the propane tanks. They must have ventilation.
Take down your basement walls, crawl in and close the doors. You will see daylight coming in through all the gaps along the frame.
I have a 3130re. There is a panel under the bottom shelf in the pantry. Behind the panel is the water heater. Again you can see daylight coming in around the edges. This requires fire retardant insulation around the water heater to block out the air gaps.
Under your kitchen island there is a panel covering your plumbing. Take it out and there is a big Triangle gap in the corner. Cut and fit styrofoam to fill the gap tight. Use gorilla tape to seal it in place.
Remove the drawers closest to the fridge. At the back where the propane and electric wiring come through to the oven there is a gap in the wall by the fridge. Remember the back of the fridge is vented to the outside. Cold air comes in through this gap. Mine is an RV fridge so I have to be careful because on the other side of that wall is the chimney for the fridge heater. I have to use flame retardant insulation here.
Make sure your inside and outside slide seals are good.

[DutchmenSport]

7 - 10 days in 20 degree temps is beyond magnificent. On mine, a 30 pound tank in 20 degree temps at 69 degrees will last about 3 days.

[rmthelen]

Trying to use the fireplace to heat to keep from freezing is not a good idea in my opinion. It will heat the living area but does nothing to heat the basement where the water system lives.

[beeje]

Originally Posted by MaxwellD

Greetings again,
Well actually - it is SILENT as a thief in the night, but my 30 gal propane bottles only last 7-10 days. My 2018 3737 FL is parked at home, but I keep the furnace on for the occasional freezing periods. I am in Texas where it has been low 30’s / upper 20’a at night so I leave thermostat at 55 degrees.
I also noticed that the heater exhaust vent blows a lot of hot air to the outside - I guess it is supposed to do that, but that seems wasteful and inefficient. What’s up with that too?
Off to buy more propane now, thanks,
Max

Your unit will more than likely not freeze at those temps since it would only be below freezing only for a few hours.

[pvcoach]

Time to winterize. Like JEFFBA said, get a compressor, drain all the water lines, and just blow them out. This has worked very well for me for 14 years. When you want to go, there is no need to prep as the lines are empty. Just go and hook-up at your next destination.

[Dam Worker]

As others have already stated a small electric heater will do wonders. You can always also put a fan in position to blow conditioned air into the basement by the bedroom stairs to keep that area warm too.

Tom

[RoadRunnerTR21]

When hooked to the house power, you might want to consider running your A/C heat pump. It keeps our unit plenty warm enough if we have one of those rare cold burst. I live about 1 hour west of you.