The Hoss 300HE indeed has two exhaust ports just above the grate in the rear of the fire box. This allows the off gasses to accumulate in the top of the firebox, which is re burned making even more heat. While this might not be "modern" gasification, it does the job. I watched this process tonight and it is mesmerizing to watch. The exhaust ports are also routed thru the water box allowing more heat to be absorbed by the water. And what Michael said. (Thanks)
I really like this furnace. It is no frills and it's not pretty, kinda like me. It looks good in the back yard too. The simplicity of its construction and the heft it has we're major selling points for me. I have designed everything from glass lined reactors, pressure vessels to heat exchangers and the like in my career, TOF met my expectations of how a furnace should be built.
Jim
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