I agree with Zak.
I have a wood stove in my cabin in Northern Mich about that size.
It will heat the whole thing to 80 degrees with only a few pieces of wood no problem.
I know that thats not the same, but the thing gets freaking hot!!!
I would think you can make that firebox work if setup right.
Might have to feed it more often, but i think it would work.
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