Stove Builder International VB00003, Installation And Operation Manual

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HE200 - Installation and Operation Manual
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4.5.5 Turning Down the Air Supply
Once the firewood, firebox and chimney are hot, you can begin to reduce the air supply for a steady burn.
As you reduce the air supply to the fire, two important things happen. First, the firing rate slows down to
spread the heat energy in the fuel over a longer period of time. Second, the flow rate of exhaust through
the fireplace and flue pipe slows down, which gives more time for the transfer of heat from the exhaust.
You will notice that as you reduce the air setting, the flames slow down. This is your indication that the
fireplace is burning at its peak efficiency.
If the flames get small and almost disappear when you turn down the air, you have turned down the air too
early, or your firewood is wetter than it should be. With good fuel and correct air control use, the flames
should slow down, but should stay large and steady, even as the air supply is reduced.
4.5.6 Building Different Fires for Different Needs
Using the air control is not the only way to match the fireplace ’s heat output to the heat demand. Your
house will need far less heat in October than in January to be kept at a comfortable temperature. If you fill
the firebox full in fall weather, you will either overheat the space or turn the fireplace down so much that
the fire will be smoky and inefficient. Here are some suggestions for building fires to match different heat
demand.