I have an older (1970s) L. Lange stove from denmark. These are great little stoves they will take a 26" log and put out a ton of heat. Mine came with the house but it was basically only the shell the previous owner had burned out the internal baffles and had a very makeshift and inappropriate steel inner stove made that was in the process of being fully burned out as well. I ended up acquiring two parts stoves in an effort to get mine correct and still had to fabricate some parts on my own. Parts are still available but hugely expensive. Anyway with the two parts stoves I was thinking I may be able to weld them together and with some modifications make a pretty efficient bell type stove. I made up a quick picture to help illustrate my thought process. The stove currently has the flue exit the back top of the stove there is a damper for kindleing and when its not pulled the air is forced to the front of the stove and back across a chamber to the flue to keep the heat in the stove longer. I would stack another stove body on top and drop a flue size thick wall pipe down from the flue which I would swap to the front on the upper stove. this would sit maybe 4" off the base of the stove inside. I would also add a baffle here shown in yellow for kindleing. Smoke path in orange is kindle and red would be under normal running mode.
also attached are the stock spec sheet on this stove as well as one for a more deluxe model which had a bread warming oven and a somewhat similar tophat design as what I am picturing although not quite the same.
Looks like it could be pretty efficient at extracting heat. The question would be, how efficient is it at combustion? Also, do you have a good enough chimney to draft with lower temperature exhaust, and will it be clean enough to not condense creosote?
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