11
WARNING! Risk of Fire!
•
DO NOT burn wet or green wood.
• Wet, unseasoned wood can cause accumulation of
creosote.
2. Moisture content
The majority of the problems fireplace owners expe
-
rience are caused by trying to burn wet, unseasoned
wood. Freshly cut wood can be as much water as it is
wood, having a moisture content of around 50%. Imag
-
ine a wooden bucket that weighs about 8 pounds. Fill it
with a gallon of water, put it in the firebox and try to burn
it. This sounds ridiculous but that is exactly what you
are doing if you burn unseasoned wood. Dead wood
lying on the forest floor should be considered wet, and
requires full seasoning time. Standing dead wood can
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
a cooling effect in your firebox and chimney system.
When combined with tar and other organic vapors from
burning wood it will form creosote which condenses in
the relatively cool firebox and chimney.
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,
check the ends of the logs. If there are cracks radiating
in all directions from the center, it is dry. If your wood
sizzles in the fire, even though the surface is dry, it may
not be fully cured.
3. Seasoning
Seasoned firewood is nothing more than wood that is
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
• Split to 6 in. (152 mm) or less
• Air dry to a moisture content of around 20%
- Soft wood - about nine months
- Hard wood - about eighteen months
NOTICE:
Seasoning time may vary depending on drying
conditions.
4. Storing Wood
Splitting wood before it is stored reduces drying time.
The following guideline will ensure properly seasoned
wood:
• Stack the wood to allow air to circulate freely around
and through the woodpile.
• Elevate the woodpile off the ground to allow air
circulation underneath.
• The smaller the pieces, the faster the drying process.
Any piece over 6 in. (152 mm) in diameter should be
split.
• Wood should be stacked so that both ends of each
piece are exposed to air, since more drying occurs
through the cut ends than the sides. This is true even
with wood that has been split.
• Store wood under cover, such as in a shed, or covered
with a tarp, plastic, tar paper, sheets of scrap plywood,
etc., as uncovered wood can absorb water from rain
or snow, delaying the seasoning process. Avoid
covering the sides and ends completely. Doing so
may trap moisture from the ground and impede air
circulation.
Heat & Glo • HST48D Owners Manual • 4012-055 • Rev B • 07/25/13
