At one point, when it was in the basement of the house, I thought the problem might be this...
http://www.gulland.ca/florida_bungalow_syndrome.htm
...and it still may be part of the problem. But now it's in a single story building with a short chimney (shrug)
I've watched it... the secondary shoots jets of flame down into the wood, burning the top into ash and coals that basically smother everything underneath. After that the air just flows over the top of the ashed-over coals (hence my opinion that air coming in from the top is stupid). Experience has taught me that air coming from under the fire, and flowing up through the coal bed, keeps them screamin' friggin' hot, burns the bottom coals first, causing the ash to fall through the grate, which exposes the next layer of coals above to the air flow. How can it possibly be "better" to pass the air over the top of the coal bed, turning the upper layer to ash, thereby limiting or eliminating air from getting to the lower coals?? In my mind, that's just backazzwards... and it sure can't make them burn near as hot (longer yeah, but not near as hot).
OK, secondary combustion makes a lot of heat... I've never denied that.
It's what happens after the secondary shuts down that I find idiotic. I'd much rather have a more even heat throughout the burn than the early nuclear blast followed by luke-warm coffee.
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