Moisture Content - Heatilator Constitution C40-C Owner's Manual

1. Hardwood vs. Softwood
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little to the other in terms of energy content. All sea-
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Hardwoods have a greater density than softwoods; a
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than an equal size piece of softwood. A cord of sea-
soned oak (hardwood) would contain about 60% more
potential energy than a cord of seasoned pine (soft-
wood).
Most softwoods are coniferous. These are trees with
needle-like leaves that stay green all year and carry
their seeds exposed in a cone. Examples of conifer-
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woods, being more porous, require less time to dry,
burn faster and are easier to ignite than hardwoods.
Hardwoods are deciduous trees, broadleaf trees that
lose their leaves in the fall. Their seeds are usually
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amples of deciduous trees are oak, maple, apple, and
birch. However, it should be noted that there are some
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woods such as poplar, aspen and alder. Hardwoods
require more time to season, burn slower and are usu-
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use the type of wood that is most readily available in
your area. However, if at all possible the best arrange-
ment is to have a mix of softwood and hardwood. This
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temperature. Add the hardwood for slow, even heat and
longer burn time.
WARNING! Risk of Fire!
• DO NOT burn wet or green wood.
• Wet, unseasoned wood can cause accumulation of
creosote.
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• Pine
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• Cedar
• Poplar
• Aspen
• Alder
12 Heatilator • C40-C Constitution Owner's Manual • 4186-900 • Rev H • 1/24
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• Maple
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• Birch

2. Moisture Content

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rience are caused by trying to burn wet, unseasoned
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it. This sounds ridiculous but that is exactly what you
are doing if you burn unseasoned wood. Dead wood
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be considered to be about two-thirds seasoned, if cut at
the dry time of the year.
Burning wet, unseasoned wood will produce less heat
output because it requires energy in the form of heat
to evaporate the water trapped inside. This is wasted
energy that should be used for heating your home. This
moisture evaporates in the form of steam which has
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burning wood it will form creosote which condenses in
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Even dry wood contains at least 15% moisture by
weight, and should be burned hot enough to keep the
chimney hot for as long as it takes to dry the wood out
- about one hour. To tell if wood is dry enough to burn,
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not be fully cured.
3. Seasoning
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cut to size, split and air dried to a moisture content of
around 20%. The time it takes to season wood varies
from around nine months for soft woods to as long as
eighteen months for hardwoods. The key to seasoning
wood is to be sure it has been split, exposing the wet
interior and increasing the surface area of each piece.
A tree that was cut down a year ago and not split is
likely to have almost as high a moisture content now as
it did when it was cut.
To season wood:
• Cut logs to size
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• Air dry to a moisture content of around 20%
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- Hard wood - about eighteen months
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conditions.