Osburn OB01520 User Manual
Page 20
Soho Installation and Operation Manual
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4.3.6
BUILDING DIFFERENT FIRES FOR DIFFERENT NEEDS
Using the air control is not the only way to match the stove’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 stove down so much that the fire will be smoky and inefficient. Here are some suggestions for
building fires to match different heat demand.
4.3.6.1
Small Fires to Take the Chill Off the House
To build a small fire that will produce a low heat output, use small pieces of firewood and load
them crisscross in the firebox. The pieces should be only 3” to 4” in diameter. After raking the
coals, you can lay two pieces parallel to each other corner to corner in the firebox and lay two
more across them in the other direction. Open the air control fully and only reduce the air after
the wood is fully flaming. This kind of fire is good for mild weather when you are around to tend
the stove and should provide enough heat for four hours or more. Small fires like this are a good
time to use softer wood species so there will be less chance of overheating the house.
4.3.6.2
Long Lasting Low Output Fires
Sometimes you will want to build a fire to last up to eight hours, but don’t need intense heat. In
this case use soft wood species and place the logs compactly in the firebox so the pieces are
packed tightly together. You will need to fire the load hot for long enough to fully char the log
surfaces before you can turn the air down. Make sure the fire is flaming brightly before leaving the
fire to burn.
4.3.6.3
High Output Fires for Cold Weather
When the heat demand is high during cold weather, you’ll need a fire that burns steadily and
brightly. This is the time to use your biggest pieces of hardwood fuel if you have it. Put the biggest
pieces at the back of the firebox and place the rest of the pieces compactly. A densely built fire like
this will produce the longest burn your stove is capable of.
You will need to be cautious when building fires like this because if the air is turned down too
much, the fire could smoulder. Make sure the wood is flaming brightly before leaving the fire to
burn.
4.3.6.4
Maximum Burn Cycle Times
The burn cycle time is the period between loading wood on a coal bed and the consumption of
that wood back to a coal bed of the same size. The flaming phase of the fire lasts for roughly the
first half of the burn cycle and the second half is the coal bed phase during which there is little or
no flame. The length of burn you can expect from your stove, including both the flaming and coal
bed phases, will be affected by a number of things, such as:
•
firebox size,
•
the amount of wood loaded,
•
the species of wood you burn,
•
the wood moisture content,
•
the size of the space to be heated,
•
the climate zone you live in, and
•
the time of year.