My outdoor wood boiler build

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Coryracing

Member
Jan 18, 2017
11
Indiana
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Here are a few pics of my 250gal pressurized outdoor wood boiler I built. I used a 500 gal lp tank and a 250gal hot water tank.
 
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How's it working out for you?
 
Neat project. What pressure level is it running? Give us a performance update.
 
It appears that the water totally surrounds the fire. Are there any fire brick or refractory in the burn chamber to insulate the fire?
 
Looks pretty good have you got any kid of baffle or chamber in the firebox, I've got a conventional box in a box that I've been modding and got it working to where I get some pretty darn good secondary combustion, about two to five minutes into a fresh load it lites the secondary and the stack goes clear and she starts making some massive heat. I'm still fiddling around with it but I am getting about 9-10 hour burns with no storage and heating a 1300 SQ Foot house with minimal insulation. My wood supply is a little wet yet as I haven't been able to get ahead much, but a neat trick is a torpedo heater for about twenty four hours set at 70. I too like the water cooled door, I really wish I would have done that when i built mine.
 
I couldn't be happier with the performance I'm getting out of the boiler I'm using about the same amount of wood I was using with my indoor unit But only loading once a day. I run about 15psi. I don't have a baffle on the 6" flue but it sticks down in the fire box about a foot and yes it does roll smoke out the door when loading. I don't have any fire brick in it but I have thought about it and may do it for next season. My line set is 1" black iron wrapped in armaflex inside 4" drain pipe. Inside the house I have a 1" copper loop feeding 4 fan coil units all on separate t-stats for zone control. I also have a plate exchanger preheating the water to my water heater. I am only running one loop currently but have plans of also heating a 30x30 portion on my barn with it by next season. It now sits farther away from the house than it did in the pic that was only temporary hooked up with pex above ground. I have only had problems with smoke in the house once. You guys seem to like my door it was more work to build than it sounded like in my head but it works well. I used 3/4 fuel swivel for gas pumps on the lines. The fire is feed by a 5" natural draft damper. My build is far from perfect you always find things you would do different next time but it is keeping my home nice and warm
 
I like your round door! does it use a fire rope or does it seal metal on metal?
 
I used a 1" round rope gasket. It seals well. I had a piece of 20" pipe laying around so that's what I used. I wish it was a little bigger.
 
I like to see people make stuff work. I see old home made Fisher-type stoves fairly often when I'm out on jobs.

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Lots of people like my door. I didn't take many pics building it here's one of the of the inside I used the piece I cut out of the 500gal tank and bent a piece of 3x1/4 flat stock around it. The outside is just a piece of flat plate with a piece of 1x1/4 stock around it to hold the rope seal
 
The round door jamb and door would tend to have much less stress than a square one. I'm impressed.

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Impressive design/Fab job. I hope those lines are insulated. Can't tell. Congrats
 
Like a well built conventional boiler. congrats
 
Glad y'all like the build. I thought about building a more complex build with cross over tubes and grates with ash drawer but talked myself out of it when time became a factor. As for a complicated burn chamber I have 2 friends with new epa boilers made by a big name brand and they don't like them so I decided to keep it simple.
 
Thats a nice job you did, keep it simple! I want to build an outdoor one this year and I like your but I'm thinking a bit smaller. You think it would be a mistake to go smaller? I would like it to last 12hrs on a fill. Also how is the smoke issue with your set up?
 
@Coryracing How are your transfer pipes working? How much heat loss? Does it melt the snow on the ground? Estimated cost? Sorry for all the questions I am building a very similar stove to yours and am stressing over what kind of piping to use.
 
@Coryracing How are your transfer pipes working? How much heat loss? Does it melt the snow on the ground? Estimated cost? Sorry for all the questions I am building a very similar stove to yours and am stressing over what kind of piping to use.
Read the sticky at the top Underground lines not the place to skimp.
If you are thinking of anything other than foam in place you don't have many choices that will perform even close to doing a proper job of foam in place.
 
posts 99 and 100...
Not the way i would do it.Foam in trench was what i was trying to emphasize.
Anything that is inside a pipe allows water some place to get in and accumulate.
Cost was a big factor where i am,foam in place was very expensive.But losing BTU's to the ground isn't cheap either.
 
posts 99 and 100...
Not the way i would do it.Foam in trench was what i was trying to emphasize.
Anything that is inside a pipe allows water some place to get in and accumulate.
Cost was a big factor where i am,foam in place was very expensive.But losing BTU's to the ground isn't cheap either.

I knew what you meant. :) I know the arguments as well.