Outdoor Wood Furnace (Work in progress..)

[purg3d]

Hello guys, I'm trying to design a system using recycled parts to provide heat to both my home and water from an outside source. It would be nearly impossible to describe the setup, so I drafted up a blue-print using Google Sketchup. The model can be found here, but you will need to download Google Sketchup to view, found here .

I plan on using a 55 gallon steel drum for the fire box, a 30 gallon steel drum for a baffle/heat exchanger and a scrapped electric water heater as a reservoir.



As you can see, the furnace itself will be encapsulated by cinder blocks, and will be filled with crushed granite (or possibly recycled ash?) for heat absorption.

The hot water tank idea is based off the design found here. If the plumbing is correct, it should rely on natural means to circulate water within the tank via a copper coil in the heat exchanger. It will be tapped into my *working electric tank in the house.

I would like to apply the same idea to heating at least a few rooms in my house. The goal is to not rely on electricity, so any laws of physics that I may be able to take advantage of would be great.

Any ideas on how I might be able to see this idea become reality? I suppose I'm looking to hear from people with experience with these things, especially building a heat exchanger and providing radiated heat from a remote source.

I really apologize for the hurried incoherency, but please look at my model and impart any information you may have on this project.

Thanks

 

[dacjohns]

How long will the 55 gallon drum last? The metal is pretty thin in them.

 

[Miltonchix]

I agree with the other Curmudgeon. If you make this you want to make it once. Build, or have built, a fire box comparable to a wood stove you'd put in your house. It will last forever and from the look of your block enclosure, you don't want to be changing burner boxes.
1/4" steel plate box would last the life of your house. Also, make the water tank easy to replace. Like all water heater tanks they rust out over time and will need to be replaced periodically.
A small inline SOLAR powered circulation pump would keep the water circulating better and you'd have a more "even" and consistent water temp.