Chris-PA
Where the Wild Things Are
I've been thinking about the draft control systems on "EPA" secondary combustion (non-cat) stoves. Our main stove is a US Stoves Magnolia, and it has a single control that limits both the primary and secondary air. This stove is located in the basement and has about a 30' flue of insulated 6" SS pipe inside a stone chimney, sealed at the top and bottom. It draws like crazy.
The Hampton H200 has a single control that limits only the primary air, and it's on decent flue but not as good as the basement.
After a couple of recent threads I've been thinking about how a primary-only system would work if I had it in the basement - it would be a problem. If I get that stove over-fired I can just about shut it down - it will still burn but not run away (and the heat output is almost scary). The total air inlet to the stove is probably equivalent to no more that 1/4" diameter hole at that point. You can see the effect of the air that leaks past the door gasket, even if it's no more than a few molecules - the faint flames lick up toward the door. So anyway, it's sealed pretty darn well. If I could not shut down the secondary air then controlling it would be difficult. I suppose I'd have to try a damper, but it would have to reduce the flue area to around what the present control does, or it would not work.
This is not a problem on the H200, as that flue does not have the draw. The H200 is newer, and I think I'm seeing that this primary-only control is the newer setup. Does anyone know why? Do any stoves have separate controls for primary and secondary air?
The Hampton H200 has a single control that limits only the primary air, and it's on decent flue but not as good as the basement.
After a couple of recent threads I've been thinking about how a primary-only system would work if I had it in the basement - it would be a problem. If I get that stove over-fired I can just about shut it down - it will still burn but not run away (and the heat output is almost scary). The total air inlet to the stove is probably equivalent to no more that 1/4" diameter hole at that point. You can see the effect of the air that leaks past the door gasket, even if it's no more than a few molecules - the faint flames lick up toward the door. So anyway, it's sealed pretty darn well. If I could not shut down the secondary air then controlling it would be difficult. I suppose I'd have to try a damper, but it would have to reduce the flue area to around what the present control does, or it would not work.
This is not a problem on the H200, as that flue does not have the draw. The H200 is newer, and I think I'm seeing that this primary-only control is the newer setup. Does anyone know why? Do any stoves have separate controls for primary and secondary air?
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