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CLEANFIRE OUTDOOR FURNACE • OWNER'S MANUAL
Wood Selection and Preparation
For the best results, it is best to burn seasoned split wood. However, it may
be possible to burn some unsplit wood with the split wood depending on
quality, size, moisture content and wood type. Properly seasoned wood has a
moisture content of 20% or less. It is darker, has cracks in the end grain, and
sounds hollow when smacked against another piece of wood. Most wood
needs to be split to dry down to 20% within a year. Wood between 4" and 8"
(10 and 20 cm) in diameter works well in most cases. Pieces of wood that are
too large can reduce output capacity because they burn slower.
• Wood that works well in most cases:
• Is between 4" and 8" (10 and 20 cm) in diameter
• Is approximately 60-70% of the length of the firebox
• Typically weighs 10-15 pounds per cubic foot for heavy heat
loads
• Pieces of wood that are too large can reduce output capacity
because they burn slower. Wood that is too long can cause bridging.
• Seasoned wood burns more efficiently, minimizes the amount of
creosote formation and reduces emissions.
• Maintain a quantity of smaller, drier pieces of wood for relighting
the fire if the wood load is burned very low or becomes completely
empty.
• Green wood contains about 50% moisture by weight. Energy is
required to heat the wood and evaporate the moisture - energy
which could have been used to provide heat for the home. The
illustration below shows that burning drier, seasoned wood
provides more energy for heating your home compared with
burning green, unseasoned wood that uses more energy to
evaporate the moisture and provides less energy for heating your
home.
NOTE: Do not store wood within the outdoor furnace installation clearances or
within the spaces required for fueling, ash removal and other routine maintenance
operations.
Before You Start Operating Your
CleanFire Outdoor Wood Furnace
Be sure to read carefully and
observe all of the information in
the entire Owner's Manual.
If any questions arise that
cannot be answered by the
information in this manual, be
sure to contact your dealer.
Seasoned Wood
With moisture content of 20% or less
Wood used to heat
Wood used to remove moisture
Wood With High Moisture
Wood used to heat
Wood used to remove moisture