Outdoor Wood Furnace Info

Outdoor Furnaces - Manufacturers with NON EPA-Certified Models Only => Home Made => Topic started by: cab on February 20, 2011, 11:28:54 AM

Title: boiler build question
Post by: cab on February 20, 2011, 11:28:54 AM

Hello-

I am thinking of building a boiler but what I have in mind is more a hybrid of a masonry heater and a fire tube boiler. In other words, build the entire boiler of firebrick, like a masonry heater, then pass the flue gas through a fire tube heat exchanger. Much less welding, and longer life I would think....Any comments?

Sketch attached....

Title: Re: boiler build question
Post by: tulenutn2o on February 21, 2011, 06:26:14 AM

Worth a try. Never really know til you try and succeed or fail. Anxious to see your progress if you build it.

Title: Re: boiler build question
Post by: jackel440 on February 21, 2011, 07:29:51 PM

Sounds like a good idea in theory.Trying to have less chance of leaks due to not have a big water jacket around everything.BUT ......Unless this was inside I think you are defeating the purpose.You will have lots of BTU's in the firebrick surrounding the burn chamber.Downside it has no water around it to transfer those btu's to.So I would think you will have wasted that burned wood to heat firebrick and then radiate out the sides and not heat anything.
I would surround the whole thing to maximize all the heat transfer you can get.
Just my thoughts on it.
Good luck with it :thumbup:

Title: Re: boiler build question
Post by: cab on February 21, 2011, 07:41:27 PM

I plan to insulate it and it will be inside, in my basement, where the leaked heat will not be wasted....

Thanks for your comments, they are greatly appreciated...

Title: Re: boiler build question
Post by: jackel440 on February 21, 2011, 07:55:47 PM

Well if it is inside then that would make sense.What kind of water capacity are you aiming for?What all do you plan to heat with it?water to air xchanger,baseboard,radiant?
If you are going to go to all the trouble to build this why not just build a gasifier?Like a Garn,Tarm or one of the others that are made for inside.Much more efficient than what you are proposing.I am hard pressed to even think about building anything other than a gasifier after building and running mine now.Plus the xperiance of a friend and his gasifier heating 2 homes and dhw.
Just hoping to get you to think outside of the box.Lots of options of what to build out there. ;)

Title: Re: boiler build question
Post by: cab on February 21, 2011, 08:10:08 PM

The plan is to have the boiler dump the heat into 1000 gallon storage tank, and to circulate that water through my floors.

It will gasify-like a masonry heater. It would be an updraft, rather than down draft, burner. Masonry heater have very high efficiencies. It is run full out with no idling....

I agree with you about gasifiers- there is really no other option....