Why did this need a vertical exhaust flue at all? I would have thought that with the huge stratification chamber, an eight inch equivalent vent at the bottom of one end of the stratification chamber would have worked just as well.
I suspect it would work well while it is really cold out until the mass started to warm up. I've wanted to try one with a horizontal exhaust at the lowest point and a chimney on an up-down tee on the end to let overly cold gasses just fall out and give a little draw when the gasses get warmer after it has been running a while. I'm not sure the heat riser I built here has enough thrust to push the gasses all the way through without the help of the heated final chimney. Kirk Mobert actually built one one time that ran the chimney down hill to cause thrust by taking all o the heat out of the exhaust. He said it worked great until it heated up.
roses are red, violets are blue. Some poems rhyme and some are a tiny ad:
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