RV Heat

[ra_weiss]

Hi. It is 10 degrees outside and not much warmer inside this Forest River 36' Sandpiper.

Slight exaggeration. But my RV is the only one I've ever owned and my propane heating system (Suburban SF-35F) can't get the inside temp above 55. Is this common? Are these propane heaters only that good or do we have an issue?

I have checked and cleared all visible venting and intake/exhaust. Unit seems to be runnings smoothly and with no racket. No major drafts

Thanks

[Jkwilson1989]

As delivered, few RVs do well in very cold weather.

Insulation and air sealing are problems in RVs when dealing with extreme cold. Skirting is nearly mandatory. Insulated vent covers help. Sealing gaps around slides with chunks of pool noodles may help.

[ra_weiss]

Originally Posted by Jkwilson1989

As delivered, few RVs do well in very cold weather.

Insulation and air sealing are problems in RVs when dealing with extreme cold. Skirting is nearly mandatory. Insulated vent covers help. Sealing gaps around slides with chunks of pool noodles may help.

Thanks, as I thought. This thing does have insulation but it's very thin, and down under not at all except for the cover. I need to design some skirting, agree that it would help.

Curious if anyone has ever insulated the under-carriage and what were the results.

[Jkwilson1989]

Originally Posted by ra_weiss

Thanks, as I thought. This thing does have insulation but it's very thin, and down under not at all except for the cover. I need to design some skirting, agree that it would help.

Curious if anyone has ever insulated the under-carriage and what were the results.

Different rigs have different construction. In many rigs, the underside of the floor serves as a plenum and air return for the furnace. Some have the lower layer insulated and some don’t. A downside to insulating is that there are several penetrations and you regularly need to drop parts of the belly to do repairs to plumbing. You want to use foam insulation, since a water leak will make a mess of fiber.

[Mudfrog]

The furnace is probably fine. The problem is that most RVs aren't designed for 10°F weather. There's some insulation in the walls but it's not enough to cope with those low temperatures. The other thing is that 36 feet offers up quite a bit of square footage to maintain. I'd bet yours has a slide or three, which if they are extended, increases that square footage to make things even worse.

There are some things you can try. I'm taking it you have electricity available. If so, invest in a portable plug in heater of some sort. Maybe two if the electricity is 50 amp service. It won't heat the whole rig up but it will help the furnace out some. Me, if there are slides, I'd pull em in if possible to decrease the space needing to be heated. If single pane glass, see about covering them with some insulation of some sort. Roof vents, stuff something into them.

The worrisome question I have,,, how big is your propane tank(s)? I'm not sure how long the propane will last with the furnace running constantly.

[SafariBen]

Not surprising. Insulating the floor or skirting is actually the last place I'd fix. You feel the floor the coldest because the body lowers circulation to the feet when cold, and the cold air leaks all come through the floor and across your feet. BUT, the warm air leaking out is where you want to focus, and that is up higher typically. The roof vents, windows, and insulation last.



My Safari has aluminum skin, and aluminum wall framing, not the greatest for insulation. Some designs are just not going to be warm.



The other issue is the capacity of the furnace, which is not likely to be reduced, but you can check to see that the flames look consistent, or check the orifice if you're comfortable with that. The BIG issue you can have is duct leakage, that is probably the first thing to check and fix.

[d23haynes57]

What is a Sandpiper? Trailer or RV? Are you at a campground and do you have park power? The heater model number indicates that it may be a 35,000 BTU heater. That would be a bit light for a 36-foot trailer. If you have power there, I would add 1 or 2 electric space heaters. That would give you about 5,000 Btus each. 2 would give the boost needed to get the inside warmer. For next year consider adding an additional heater. Maybe 20K.

[Parafango]

I specifically added an outlet inside my rig, that connects to a 20 amp cord I can plug into the power pole outside in addition to the 30 amp shore cord. It has it's own circuit breaker in the rig. I use this to supply power to an auxiliary electric heater. I was getting close to the 30 amp circuit max when the refer, water heater, furnace were all demanding power, (not to mention coffee maker and microwave) so I added the outlet to connect directly to the power pole. This helps supplement the heat BUT,

I'm not sure if others have mentioned it here that the heater ducts under the floor, help keep the plumbing from freezing by heating the spaces in the covered area under the rig. Supply too much supplemental heat using electric heaters and don't circulate it through the ducts, and the pipes, gray/black tanks, a fresh water may freeze.

A good ceramic heater will work.
In case you haven't see this on YouTube, here's a link to a guy that buys and tests all kinds of things including heaters. It's fun to watch anyway,

Project Farm tests heaters

[jacwjames]

Propane heat isn't really that efficient, 55% efficient meaning about as much heat is going to the outside as inside. You will be burning through a lot of propane trying to stay warm.


If you have access to electrical shore power the fastest easiest thing would be to go buy a couple of small heater.



Close all you slides, open all your base cabinets to prevent pipes from freeaing



Block any of the ceiling vents to prevent heat from escaping


Get some https://www.lowes.com/pd/Reflectix-R...5-ft-L/1014123 and cover all your windows when it's cold out, or most of them.



Long term you could look at insulating the underbelly of the rig but that's a big project.

[ra_weiss]

Appreciate the replies.

I'm on solar w/o ton of solar (as you can imagine). In the winter it takes my 14kw battery bank all day to top off so using a 1000-1500w heater is kinda out of the question. Nor would I want to use backup generator for this purpose.

re: leaks in the ducting: That's what I was thinking because I can't believe running the propane heater all day fails to top 55 degrees. I'm not sure that is the case though because if there is a leak a mouse certainly would have setup shop inside by now (I trap about a half dozen per year). I've never seen or heard one in that ducting.

Re: leaks around slideouts, windows, etc.: Nothing obvious around slides or windows. Seems the greatest leak is around the (replaced) fridge. Will use foam insulation to resolve that. There also is quite a draft coming from under sink of which doors are open to avoid water pump and tank freezing up. trade off.

In the end I think it's pretty much as assumed: A poorly insulated camper.

[jacwjames]

I bought a Mr. Heater Big Buddy heater. I had an extendastay type hose off my propane tank for grill already so I just bought an extension and cut a hole up from the basement into the LR area under a cabinet.
I can hook the Big Buddy up and use it. It will generate alot of heat but will also produce moisture. I usually don't let it run all night, just slept under a bunch of covers. But during the day it was nice to have that heat available.


https://www.homedepot.com/p/Mr-Heate...yj863peI&gQT=1

[ra_weiss]

Originally Posted by jacwjames

I bought a Mr. Heater Big Buddy heater. I had an extendastay type hose off my propane tank for grill already so I just bought an extension and cut a hole up from the basement into the LR area under a cabinet.
I can hook the Big Buddy up and use it. It will generate alot of heat but will also produce moisture. I usually don't let it run all night, just slept under a bunch of covers. But during the day it was nice to have that heat available.

I would have done that but what about its fumes? You can't run those inside.

I had thought about adding a small kettle stove, and would have one right now except I live in TX and the only time it gets this cold is when one of those damn arctic vortexes show up. So, not really practical.

[Parafango]

Originally Posted by jacwjames

I bought a Mr. Heater Big Buddy heater. I had an extendastay type hose off my propane tank for grill already so I just bought an extension and cut a hole up from the basement into the LR area under a cabinet.
I can hook the Big Buddy up and use it. It will generate alot of heat but will also produce moisture. I usually don't let it run all night, just slept under a bunch of covers. But during the day it was nice to have that heat available.


https://www.homedepot.com/p/Mr-Heate...yj863peI&gQT=1

The item in flames in my post is a mister heater, see the video at 15:22
I won't have one of these in an enclosed area, like my rig...

[ra_weiss]

Yeah, after reading about its "oxygen depletion sensor" (which shuts it down if O2 reading falls below 18.5%) I asked AI if it or other propane heaters with oxygen depletion sensors are good inside. It literally called me a fool and said don't.