posted 14 years ago
Hmm a Russian furnace,, I have built somewhere around 18,, did some experimenting on my own and checking out what worked best and so on,,
Albi Barden is a great place to start,, I attended one of his workshops in Montana years ago,, one of the things I noticed in some drawings is the chimney is part of or is supported by the heater. I found that it is best to have them separate due to the expansion of the heater itself. I would be glad to share my experiences with you if you wish. Google has tons of hits for Russian Wood heater, furnace, masonry heater, Finish heater and on and on. I found a good balance with materials in regards to mass and a good expansion joint in the heater will prevent any major expansion cracks. Kept the customers happy.
The first one I built back in the early 80s was for the local county extension agent. He kept track of temperatures inside and out at the top of the chimney for a year and came up with a 96% efficiency. I built a small 3 flu in my home and tested it. Efficiency was near 80%. Anyway,, let me know if I can be of help.
M&J