Improving heat in a cargo trailer.

[barrysuperhawk]

I have a cargo trailer that I camp in occasionally. I have installed AC in the roof for when its hot, but I don't really have a good solution for when its cold. I have tried little milkhouse electric heaters but it ***** when they pull too much from shore power and pop a breaker and you wake up freezing. I have also tried buddy heaters with a CO alarm but they seem to generate alot of condensation and I think if I insulate better that will just put the condensate in the walls instead of on them. I have other reasons for not really wanting to insulate the walls too, so I need to size my heat source appropriately. I might only spend a couple nights a year camping while its cold enough to need this, so I don't need full on RV heater and even one of those combo rooftop units seems excessive.

Then I discovered those chinese knockoff diesel heaters on you tube, but there are hundreds of them and I don't know which one I might want. I am shakey on 2 points, first which exact one to choose, (there are a TON of them on Amazon) and second, how to mount it. If I put it in a metal tool box on the tongue of the trailer, and just cut a hole to duct the heated air in, I don't lose any cargo space, but do I cause other problems? If I mount it inside, then I have to deal with both the exhaust and fuel delivery (I don't want diesel inside the trailer with me if I can help it) so maybe some kind of quick connect for the fuel and use some type of a boat tank?

So, what do y'all think? Are any of those made up chinese brands any better or worse? Any suggestions are welcome.

 

[P51Mustang]

A lot of RV roof top air conditioners have the option of a heating element (the one on my car trailer has the option but I do not have it). It could be something to look into. Heck, it could even already be on the A/C unit that you have. I do not have any idea of how well they work.

 

[bluedog225]

I insulated my 6x12 wells cargo with Mylar then 3/4 Polyiso. Put in a little tiny tot coal stove. I run it with oak lump charcoal from Costco.

Works great. Dry heat. No breathing all the carp from exhaust.

Warms for about 4 hours per load. Can burn wood in a pinch but it is sparkier and harder to load.

Not too hard to set up the chimney. Use silicone roof boot.

 

[barrysuperhawk]

Yeah my roof AC was salvaged off a teardown RV, so its old enough that if it breaks, I cant even get parts for it anymore, so thats a no go. More importantly I am wanting something that does not rely on shore power for the heat. I have already used buddy heaters and little portable electric heaters. The buddy heaters are OK, but if you hook to a big bottle so it runs all night, the bottle freezes outside... its never set off my CO alarm in the trailer, but it is still an open-ish flame inside the trailer, so I am always a tad paranoid about them.

I know a guy that runs a full on pellet stove in his RV but I wasn't looking to dedicate that much space. I was thinking if I got one of these diesel heaters it would be safer AND more efficient, and I could run it off 12v battery or a jackery or even the 12v output of my mini generator....

 

[PugetDude]

Look at a wall mounted marine pellet stove- used in boats in the Pacific Northwest. Dickinson is one brand; there are probably others.
My neighbor had on in his harbor tug- it was wall mounted, about the size of a shoebox- vented through the wall.

 

[P51Mustang]

Here is a video on putting a diesel heater into an off road camper set up:

 

[barrysuperhawk]

Ok, so to ressurect my thread, I ended up getting one of those 8K (yeah right) Dhinese diesel heaters for my trailer. I am currently vacillating between putting it in some type of tongue box or mounting it inside. In a tongue box, all of the fumes are outside my living space (both the fuel and the exhaust) but I have to duct the warm air in to the trailer through the wall of the box and the trailer, and I am not sure how the controls will work. If I mount it inside then I have to get the exhaust out, fresh air in. I also worry about installing something fragile that takes up space into what I use most of the year as a regular cargo trailer. I think if it's inside, I also want the exhaust and fresh air piped farther out from under the trailer - maybe black iron pipe to run the exhaust away from the bottom and protect it a bit?

Anyway, when I decide my plan, I will document here, but in the meantime I welcome opinions on the inside/outside mounting options

 

[PugetDude]

One vote for Tongue mount, outside the cargo box.

 

[theoldwizard1]

I have also tried buddy heaters with a CO alarm but they seem to generate alot of condensation ...

Combustion of most fuel produces H2O as water vapor. Combustion of propane US THE WORST !

If I mount it inside, then I have to deal with both the exhaust and fuel delivery (I don't want diesel inside the trailer with me if I can help it) so maybe some kind of quick connect for the fuel and use some type of a boat tank?

Those diesel heaters work great. Lots of videos on YouTube.

Mount it inside as close to fhe ceiling as possible (less likely to be in your way). If possible, run the exhaust pipe the full length of the trailer. FREE bonus heat, but put some kind of guard around it so nothing can directly touch the exhaust pipe. It will ignite combustible items.

Boat tank outside is good, but you will need a small fuel pump.

 

[dcg9381]

Anyway, when I decide my plan, I will document here, but in the meantime I welcome opinions on the inside/outside mounting options

Interested to see how this works out. Is your cargo trailer insulated? That's soon-to-be on my project list.
RecPro AC units are heat pumps, which pull pretty good power and only work down to 30s or so.... Other units have resistive heat, but same problem, big power pull....

Our main issue is cooling... Curious to know how much insulation you have for heating and how your alternate source works.

 

[ambenz]

I've seen these and they are easy to operate and if something goes wrong, you have a American Manufacture you can go to for parts! I BIG plus compared to some Chinese thing...good luck getting parts for that!!!

Dometic Mojave Small Doored Furnace 16,000 Btu​

Had one of these in my 20 Ft travel trailer, it worked great using propane with NO inside living space combustion.
And that is what you want. You may have to make a cut out on the front of the trailer and make a little box to install it in, but I am sure you are handy or else you wouldn't be here.

 

[Sumboodie]

Have 2 of the Webbasto heaters in the 30ft box on my delivery truck. No trouble keeping it warm when it's -40*

I was considering putting one of the Ling Long Dong ones in my TDI car as the heater ***** but no one will ship to here.
Ironic as I'd guess AK probably would be one of the highersales states of them.

 

[barrysuperhawk]

Wow, what a difference a(nother) year makes..

So, I still have not installed the heater on my Cargo trailer, but I am back on this project. Forgive me for re-hashing some earlier questions, and I have watched a ton of youtube, but alot of life has happened since I have thought about it.

So I need to make some choices, and I would like some opinions for MY install. I am not planning on doing any ******** camping, this is mostly to have a place to sleep at events instead of using motels. 95% of this trailers life is hauling cargo, helping folks move, even hauling my golf cart.

My Current decision is inside or outside.
Inside means I have to get combustion air in, and exhaust out and plumbed somewhere safe.
Inside means I have combustion taking place inside an enclosed space where I am sleeping.
Inside means I may have to smell the fuel I use If I have any spillage or even just in general. I am considering only using kerosene for this reason.
Inside means I am heating and re-heating inside air and should be more efficient overall at actually warming the air.
Inside means I am listening to whatever noise this thing makes or I am changing the fuel pump.
Inside means I am taking up interior space that I otherwise would use to haul cargo (my main use for this trailer) when I am not camping.

Outside has 2 possibilities, permanently MOUNTED on the trailer like the AC unit or standalone outside like the tent campers do.
Mounted outside means I need to deal with protecting the unit from damage while travelling.
Mounted outside means I have to decide whether to heat outside air and blow it in (one hole) which is going to be less efficient depending how cold ambient air is.
Mounted outside using one hole means I may also have a chance of sucking up exhaust with the heated air intake.
OR
I have to cut 2 holes and pull inside air out to heat and then blow the warmed air back in should be more heat efficient, but, well, 2 holes.
Outside means I need to protect the heater from any elements both while camping and while not camping.
If its permanent mount outside, then protection from elements is a real concern.
If it is some type of temporary mount, then is it on the trailer - hung off the side, or just sitting on the ground somehow, tent camper style.
Outside mount also needs to deal with plumbing and separating the combustion intake and exhaust ports away from each other.
Outside Mounted on trailer means I have to safely support it, and make it easy to fill up and operate.
Outside Mounted on trailer means I may have to listen to any transmitted sounds through the frame.
Outside NOT mounted means I need to come up with a way to support everything while deployed, then how to transport everything.

So, have I missed any concerns or advantages of either option? I am leaning toward the outside option because I am VERY sensitive to odor and I use a CPAP so any smell tends to be concentrated. So, I am trying to only do this once, and not make any mistakes I have to take apart and fix. So, lemmie have it, what are your opinions?

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