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[AirForcePOL]

Hello everyone,
I was on this forum a few years back when I was thinking of buying a woodmaster 4400 however, I decided to put up my 36x45 building instead (which I am glad I did).   I have decided that I am going to build my own wood burner.  I recently came across a website that sells OWB plans for around $30.  The designs are pretty simple but I am worried that the design I am interested in building will not produce enough BTU's for what I am wanting to do.  I will be heating my building with R-19 in the walls and R-50 in the ceiling which should heat pretty good as well as my 1500 square foot house which is 80 years old and drafty.  I recently blew in R-50 insulation in the ceiling which I'm hoping will pay off this winter and help with heating costs.  I dont plan on heating domestic water as of right now.  The firebox on the design is 20 cubic feet and will hold approx. 90 gallons of water and is estimated at 125,000 BTU's.  Do any of you think that will put off enough heat to heat my house and building?  if not, any suggestions on improving the BTU output?  I thought about changing the design and making both the firebox and water jacket larger, and also running the water return through a series of pipes inside of the firebox.  Below is the link for DEB Designs website, I have been looking at the "Outdoor Wood Stove Plan IV"  http://www.deb-design.com/  any input would be very helpful.  Thank you in advance,  Alex.  P.S.  I live in central Illinois if that helps at all. 

[Larson88]

 just about any stove will put out enough heat to heat your house, its just a matter of how often you fill the stove. Once a day is ideal i cold weather but 2 or more fills a day is just a pain. I would have to say that adding more water storage to the plan would help along with doubling the amount of insulation they say, i built my own boiler and it holds 200 gal of water and last week i even had snow on the roof of the boiler, i built a big cage around my boiler so i was able to insulate it real well, im very happy with my build its simple and works great.

[jackel440]

My opinion on the subject is the need for larger amounts of water storage,but you also need a design that will most efficiantly burn the wood and capture the btu's the wood is putting off.
There is nothing wrong with plans,but I would study what has already been done.No point reinventing the wheel when it has already been done.Plus theses companies have spent time and money on R&D.Go look at the EPA test and see what model were tested and how they performed.Then look at how they are made ,and incorporate the features that seem to work from each stove.That's what I am doing on my gassifier.I personally would not consider building anything but a gassifier.I know it's more work,but the benefits are great.
Good luck

[Larson88]

jackel       is it true that you cant burn green wood in a gassifier? Cause im very happy with my build, simple and can burn any thing i want in it!

[AirForcePOL]

Thanks guys...  I'm not really too worried about how often I fill the stove but if I only have to fill it once a day it would obviously be better two.  I'm not sure if you guys looked at the website I found the plans on or not but the stove I'm looking at has a natural draft intake on it.  I would probably change that to a blower and build maybe a little bit bigger firebox and water jacket.  I like the concept of having a round firebox but don't want to pay too much to have someone roll and weld two cylinders for me as I am trying to build a fairly inexpensive stove but at the same time try not to cut too many corners.  I thought about just having a round firebox and a square water jacket.  I wouldnt even know where to start building a gassifier but from what I have read it would probably be well worth the extra work.  The plans I found dont look like there is much room for insulation so like Larson said I will probably change the design to add as much insulation as possible.  Another question is the door...  do you guys think sand filled would be ok or should i stick with the water filled door that the plans show?  There are so many different ways to build a stove I dont even know where to start!! I will hopefully be starting on it sometime within the next couple of months after the holidays when I actually have some money left over for myself! Thanks for your input on this I appreciate it. 

[willieG]

jackel       is it true that you cant burn green wood in a gassifier? Cause im very happy with my build, simple and can burn any thing i want in it!

will it burn green wood...i don't know , maybe but if you are burning green wood in any stove you are wasting energy and lots of it
green wood is near or higher than 50 percent moisture.
below is a paragraph taken form a professional on a wood burningn forum, good read about green wood.

It is also useful to note how these concepts apply to un-seasoned (green) wood fuel. If only seasoned a short time, 50% moisture is a realistic figure. Then a two-pound piece has one pound of wood fibers (worth 8660 Btu). There will be 1.54 pounds of water to vaporize and heat up (taking away 2200 Btu). The two-pound piece has a net available energy content of 6460 Btu or 3230 Btu/pound. This is only HALF of the available energy present when burning seasoned wood. Green wood consumes the bulk of its energy just to keep itself going, and is obviously subject to easily going out.

[jackel440]

Yeah you can burn green wood ,but it defeats the whole purpose of the having a giisifier.Just like willie said it will use up the energy drying the green wood to get a good burn.Causing you to lose efficiancy.
Now I could in theory burn all kinds of crap in mine too.As I will have a big bypass chamber so in effect mine will burn like a regular boiler if I leave it open.
You definately want to use seasoned dry wood.

Back to the original poster...I would skip the water in the door.Too much hassle ,and places for leaks to start.I would make a door with refractory brick in it or K-wool packed inside it.That's what we use on our heat treating furnace and it work excellent.Our plant is the largest heat treating operation in the U.S.  The only water in our furnaces is a water jacket flowing around a circulating fan' bearins in the heat treat chamber.Your not burning that hot so I see no need.Your door if thick enough and with the right amount of brick or K-wool it will be fine.Remember K.I.S.S. theory.you will be much happier.