In the planning

[4seasons]

New guy here in the planning and design phase. After learning about masonry heaters on another forum I started scouring the web for more information. That is when I learned about RMH and that search lead me here. So now I am trying to figure out the best way to replace my current wood stove with a multi-function RMH.

I have read tons of different designs and ways to build these and am just trying to figure out how the best way to make everything work. I am planning to install right where my wood stove currently sits and use my existing chimney. And that is where my dilemma begins. First this area is 42" deep and 92" long on an exterior wall and raised on a brick pad. The opening to the chimney is 26" up from the pad and almost centered lengthwise. It is only a 6" thimble though.

After seeing some of Matt's builds and reading about the trouble Manny is having with his 6" system I am thinking about building a 8 inch batchbox system, but am unsure if I can use it with my 6 inch chimney. Next, after showing some of the builds to the wife she really didn't like the cob and barrel look so I am going to try to scrounge up some used brick to build with. My next though is I would love to have both a white oven and a cook surface. I am unsure of how to make that work or even if it is possible. Seems like the few I have seen with a white oven have the oven over the riser where the top of the barrel would normally be. Can an iron plate be used on the top of the riser for a cooking surface and still have enough heat to put an oven in a bell?

Next idea I had was to feed the system with outside air. My current wood stove is horrible about burping smoke back into the house and I think an outside air source would help. This means I would need to fit an air tight door on the front of the box and feed air up from below. Has anyone tried this before?

Finally because of the limited footprint I am thinking of a small bench only 4-5 ft long. I have not been able to find any designs with both a bell and a bench or if there is a minimum to reduce a 8 inch system down to a 6 inch chimney. Can anyone point me to some related reading on this topic?

Thanks in advance for any help. I am hoping to get the prototype built this spring.

[matt walker]

Welcome! Man, that is one whole big batch of questions. It sounds like you've been reading over at Donkey's board already judging by your grasp of what's possible. If you haven't, that's where I'd recommend you do some searching and reading.

If you are thinking of a batch type build, 6" will be plenty. That type of front end puts a whole lot more heat into the mass than a J style in the same size. You can for sure do a bell/bench combo, whether it's one bell that has a leg for the bench, or a bell and bench flue run, or really just about any combo of those. I think you can accomplish all your goals in a build, door, outside air, oven, cooktop, etc. Cooktop height being a bit high is an issue that's hard to get around with this kind of burner, but, there are ways to mitigate that.

[4seasons]

I have done a lot of reading on Donkey's board. I pulled a few ideas from there but I have yet to find a build that will accomplish all that I want. I really love all the "outside the box" thinking that is going on with these, but at the same time I am wanting to be cautious and use something that will work for many years and not burn the house down. I just know that my current wood stove is not doing its job anymore as I have had to patch it up twice this year already. Even as I type this I am fighting to get the house up to temp. I am really hoping that putting some heat into mass will stabilize my indoor temps.

[pa_friendly_guy]

How large is the area that you are trying to heat 4 seasons? It will be some what difficult to incorporate a heating stove, a cooking stove, an oven all in one unit, you will have to be way outside the box. The outside air supply should be no problem, the heating unit should be no problem. Getting and oven as well as a cook top in one unit could be a challenge. One or the other I see no problem, but getting both stretches the available heat source to the max. Talking out loud here, and not being an expert, maybe try Matts slanted design on the heat riser, with the oven unit built on top of the barrel. Then maybe incorporate the cook top into the top of the oven by putting a metal plate at the top of the oven. By slanting the heat raiser you save a lot of height so your cook top surface might be able to be kept at a reasonable level. The oven would not be very well insulated with a lot of heat escaping out the metal cook top, but it might work. This is for discussion , so its just an idea, can someone point out the potential problems with this idea. I would be glad to listen and learn.

[pa_friendly_guy]

While I am thinking outside the box, what if you forget about using a barrel in your build and go with a masonry design . Use Matts design of slanting the heat riser to keep the height reasonable , build the unit out of masonry, when the flames exit the heat riser have then hit the metal bottom of the oven. Make your oven out of a metal closed box with a good door. Then take the heat and smoke across the bottom of the unit, up the left side, and across the top of the oven . Just above the top of the oven is your metal cook top. Keep your clearances big enough to handle the draw. Then the exhaust exits down the right side of the unit and into a bench or a bell of what ever you choose to hold the heat. That could give you the white oven, cook top above, and heat from the bench and radiating from the metal oven. The cook top would still be a bit on the high side for easy convenient use, and the hot oven door would be right in front of your belly as you tried to use the cook top. But it may incorporate all 3 of your goals in one unit. Again, I am just talking out loud here, I have no real experience or real time knowledge working with these units. Like you I am a Dummy who has just been hanging around these boards for awhile. Just enough knowledge to be dangerous. Again, if any one sees glaring holes in this design please let us know.

[4seasons]

I'm not too worried about countertop height. The cook top would mainly be emergency and backup use. I really do want the oven too be insulated so it will hold heat well after the fire is out. But you may be right in me not being able to get both in one build and have either work well. I need to read up more on the oven and how to get the right heat to work well.
I am already planning on not using a barrel as the wife hates the look.

[pa_friendly_guy]

Are you thinking about something along these lines?

http://www.youtube.com/watch?v=LuZzgrNPq_k

They have the advantage a low fuel demands, good thermal mass to retain heat, incudes an oven in the design, the only problem is a cook top. It certainly would make your better half happier, and lets face it, when Mommas not Happy, aint Nobody Happy. Here at my place I deal with this type of " Zoning " issue all the time. Some here on this board have suggested I try to Bribe the Zoning officer with a new pair of shoes. I have found it better to comply, it makes life simpler. When I 1st got married her Uncle told me that the 1st 10 years where the hardest, Let me tell you something, I have not found it to be getting any easier.

[matt walker]

Here's a nice example that's close to what you describe.

http://donkey32.proboards.com/thread/87 ... er-heating

[DevilsBrew]

[4seasons]