What is recomended heating a semi trailer?

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vwguy

New Member
Dec 21, 2008
4
BC
We are tying to heat a 50' semi trailer that has 1" plywood fiberglass walls and a steel roof with 1" insulation, floor is a solid 1 1/4" wood, all air gaps are filled so it is air tight, just does not have a very good insulation value . We are using this for wood storage for our business and needs to be heated, the warmer the better for the de-humidifier. We have a Pacific energy super 27 in there right now , the temperature variation is a yoyo. We have to load the stove every 2 hours or if we let it go for 4 hours ( like every night so I can sleep some) , we loose 6 -8 degrees temperature. It seems that the temp will only rise when the stove is wide open for the first hour, then the temp starts to drop back down. We have the same stove in our house and it heats us out of there so this is the reason we bought the same one for the trailer since our house is 2000 sqft and the trailer is 400sqft....5 times smaller... I assumed it would be plenty.....I was very wrong, we need more heat.

Everything is new including the 6"flue, so it would be nice to find another stove that also uses the same 6" flue.

I was looking at a Blaze King princess and am not sure if the princess will be good enough to keep the temperature more consistant. I would just like to get a longer burn so I can sleep longer at night and keep the temp relatively the same over a longer period.

Will the Princess do this for me?

Any sugestions would be appreciated, we just can't insulate the trailer better as we had shelving custom built floor to ceiling and they are full which makes for an imposible re-do until summer, I would rather just get a larger stove as the firewood supply is not an issue.
 
Tough one to call. Unfortunately it sounds like the issue is solely the insulation. Just about any stove should run you out of 400sqft. Before buying a new stove - what about buying some faceless fiberglass batt insulation so the moisture could still leave the wood and stuffing it in everywhere you can get it along the walls? I don't know how much this would inhibit wood drying - just brainstorming here. Or maybe some foam board insulation, thicker the better, and attach it to the outside of the trailer walls. It would take some doing to make it look pretty, don't know if thats important.

It sounds to me like make your new stove choice purely on firebox size if there is no way to insulate the walls and still allow the wood to dry. With so much heat going through the walls, all you need to look for is something that will be on fire for as long as possible. My f600 will stay up over 300* stovetop for 9+ hrs, and I'm not sure even that would be enough for you. I would say the biggest box of fire you can find would be the ticket.
 
The more I think about it - the foam board insulation may be the ticket if the trailer can stay stationary for the winter. I would say get enough to cover the trailer's walls outside, I think you can get 2" foam board as high as r16, wrap it up tight in housewrap and call it good. When summer comes you can number the foam boards with a marker, store them inside and use them again next winter. May need to lag bolt a nailer or something on either side of the door to hold the housewrap in place. I think you'll spend the money on a new big stove and find that you have the same problem - unless there is a raging fire going you're out of luck.
 
IMHO, wood stove heating in general tends to have wider temp swings than other modes of heat like gas, electric, oil, etc. You need to have a well tended stove for even heat. The lack of insulation in your space would only add to that problem. I don't know that any brand of wood stove would correct the issue as they would all need to be maintained fairly regularly to provide even heat.

If you want to stay with wood - versus gas, electricity, oil, (which would be easy to regulate temp) you may have better luck with a wood boiler and storage tank outside the trailer. This would have the ability to store heat and release on demand to the trailer, which would help moderate the temp.
 
I was thinking you could park it inside a canvas roundtop shelter and then drape rolls of fiberglass insulation over the trailer. Insulated tarps are another option. Rigid foam board although expensive, would work well.
 
You mention that the trailer is airtight, could the stove be starving for air after you leave it alone? Our code in CT. requiers one square inch of makeup air for oil burner per 1,00 BTUs of output. I don't have a clue how it applies to wood stoves.
 
Outside air for the stove would be a good idea. I'd strap 2" foam insulation board on the top of the trailer. Strap it well or it will be airborne in the first big storm.

In lieu of that a Blaze King Princess should deliver longer burns.
 
Yes we have outside air make up from under the bottom of the stove, a 4" hole, which is the same as our house, the piping is also the same as our house, two wood stoves installed the same, but the outcome for both is completely different.. I have thought about insulation on the outside of the trailer, but would rather not do that because of how windy it gets here many times a year. Sorry this is a rush post I have to leave right now, will have to check back later this evening
 
LLigetfa's idea of parking it under a roundtop canvas would solve the wind issues - though I suppose price wise between the canvas hoop house and the insulation we're probably getting up there. I bet even the (relatively) dead air space between the canvas and the trailer would go a long way towards giving you the insulation you need to keep things warm in the trailer. A plastic covered hoop house might be a good middle ground, lower cost than canvas and would block the wind allowing you to insulate outside the trailer with fiberglass (lower price) instead of foam.

Could probably rig something up with foam board on the walls and rope / ratchet straps that would hold it in place pretty darn good too. I'm still leaning towards insulation vs. a bigger stove. Any warm block of cast iron should keep an "airtight" 400sqft space toasty for 8 hrs - you shouldn't need a 500lb stove in there. Could even try insulating just the side that faces the prevailing winds and see what it buys you.
 
So basicly this tractor trailer is your wood shed? You are heating the wood by burning wood to dry it faster for your business? Is there any other reason it needs to be heated other than for the dehumidifier? It would probably dry even more if kept dry and partially covered but subjected to those harsh winds. It just seems you are robbing peter to pay paul with your current set up.
 
roac said:
So basicly this tractor trailer is your wood shed?

"floor to ceiling custom shelves" in the trailer - I gotta' assume milled wood or some such thing drying.

It's not just a big firewood shed, right?
 
vwguy said:
Yes we have outside air make up from under the bottom of the stove, a 4" hole, which is the same as our house, the piping is also the same as our house, two wood stoves installed the same, but the outcome for both is completely different.. I have thought about insulation on the outside of the trailer, but would rather not do that because of how windy it gets here many times a year. Sorry this is a rush post I have to leave right now, will have to check back later this evening

The insulation will hold if securely strapped. I would put 2 straps on a 4 x 8 sheet. Run a 1x3 plank on each outside edge, parallel to the trailer side, under the straps to uniformly hold down the insulation.
 
I think even 1/2" or 3/4" polystyrene would make a big difference . You could screw it to the inside and put the ply wood over it . Once you get the wood warm it should stay warm over night .
 
meathead said:
roac said:
So basicly this tractor trailer is your wood shed?

"floor to ceiling custom shelves" in the trailer - I gotta' assume milled wood or some such thing drying.

It's not just a big firewood shed, right?

Yeah after re-reading it a few times I think you are right. My brain just went the wrong way. It seems to do that a lot now!! :lol:
 
Thankyou for the ideas, I think we will put up some styrofoam as thick as we can buy. I really appreciate your input. Thankyou
 
If you buy the cheap beaded stuff, be aware that it will take on water and diminish the R value. You might want to protect it from moisture.
 
I forgot all about this post. Anyway what we did was put 2" plastifab styrofoam on the ceiling + the 1" that was allready there, and left it at that for now. Also replaced the super 27 with a BlazeKing king. WOW...when it was minus 18 outside, the trailer would get up to 18 degrees inside. I can go 12 hours with the stove burnig wide open on a fill up, not much more than this though, 12 is max, not to many coals left, 10-11 hours is perfect, nice amount of coals, and the fire starts right up while I'm still loading the stove. I can now sleep at night. We use about 18 pcs of wood a day, thats 7 or so large pcs each fill up, and then I throw in abouot 3 - 4 pcs about mid day, which helps keep the trailer temp consistantly higher before going into the evening. One thing I do not like about the King is the flue intake is lower than the door opening inside the stove, so when my wood catches on fire while loading, a ton of smoke fills the room instead of going up the flue, I think it is a very poor design, as no amount of draft will suck this much smoke back in. So I am going to have the stove modified this summer to add an extension above the stove to bring the flue opening higher than the door opening so that the smoke will naturaly go up the flue instead of out the door.

Thanks for all the advice. Next step is to insulate the floor, but for now, it is ok the way it is. A huge improvement as to the way it was.
 
vwguy said:
One thing I do not like about the King is the flue intake is lower than the door opening inside the stove, so when my wood catches on fire while loading, a ton of smoke fills the room instead of going up the flue, I think it is a very poor design, as no amount of draft will suck this much smoke back in. So I am going to have the stove modified this summer to add an extension above the stove to bring the flue opening higher than the door opening so that the smoke will naturaly go up the flue instead of out the door.

Increased draft should solve the problem without changing the stove. Altering the innards of the stove may modify its burning. I'd add more stack (with bracing) instead.
 
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