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HEATING
Controlled combustion is the most efficient technique for wood heating because it enables you to select the type
of combustion you want for each given situation. The wood will burn slowly if the wood stove air intake control is
adjusted to reduce the oxygen supply in the combustion chamber to a minimum. On the other hand, wood will
burn quickly if the air control is adjusted to admit a larger quantity of oxygen in the combustion chamber. Real
operating conditions may give very different results than those obtained during testing according to the species
of wood used, its moisture content, the size and density of the pieces, the length of the chimney, altitude and
outside temperature.
EFFICIENCY
Efficiencies can be based on either the lower heating value (LHV) or the higher heating value (HHV) of the fuel.
The lower heating value is when water leaves the combustion process as a vapor, in the case of woodstoves the
moisture in the wood being burned leaves the stove as a vapor. The higher heating value is when water leaves
the combustion process completely condensed. In the case of woodstoves this would assume the exhaust gases
are room temperature when leaving the system, and therefore calculations using this heating value consider
the heat going up the chimney as lost energy. Therefore, efficiency calculated using the lower heating value of
wood will be higher than efficiency calculated using the higher heating value. In the United States all woodstove
efficiencies should be calculated using the higher heating value. The best way to achieve optimum efficiencies
is to learn the burn characteristic of you appliance and burn well-seasoned wood. Higher burn rates are not
always the best heating burn rates; after a good fire is established a lower burn rate may be a better option for
efficient heating. A lower burn rate slows the flow of usable heat out of the home through the chimney, and it
also consumes less wood.
• Never over fire your stove. If any part of the stove starts to glow red, over firing is happening. Readjust the
air intake control at a lower setting.
• The installation of a log cradle or grates is not recommended in your wood stove. Build fire directly on
firebrick.
• Never put wood above the firebrick lining of the firebox.
• Attempts to achieve heat output rates that exceed heater design specifications can result in permanent
damage to the heater.
VISIBLE SMOKE
The amount of visible smoke being produced can be an effective method of determining how efficiently the
combustion process is taking place at the given settings. Visible smoke consist of unburned fuel and moisture
leaving your stove. Learn to adjust the air settings of your specific unit to produce the smallest amount of visible
smoke. Wood that has not been seasoned properly and has a high wood moisture content will produce excess
visible smoke and burn poorly.
CREOSOTE FORMATION AND NEED FOR REMOVAL
When wood is burned slowly, it produces tar and other organic vapors, which combine with expelled moisture
to form creosote. The creosote vapors condense in the relatively cool chimney flue of a slow-burning fire. As a
result, creosote residue accumulates on the flue lining. When ignited this creosote makes an extremely hot fire.
The chimney connector and chimney should be inspected at least once every two months during the heating
season to determine if a creosote build-up has occurred. If creosote has accumulated (3mm or more), it should
be removed to reduce the risk of a chimney fire. We strongly recommend that you install a magnetic thermometer
on your smoke exhaust pipe, approximately 18" above the stove. This thermometer will indicate the temperature
of your gas exhaust fumes within the smoke exhaust system. The ideal temperature for these gases is somewhere
between 275°F and 500°F. Below these temperatures, the build-up of creosote is promoted. Above 500 degrees,
heat is wasted since a too large quantity is lost into the atmosphere.
TO PREVENT CREOSOTE BUILD UP
• Always burn dry wood. This allows clean burns and higher chimney temperatures, therefore less creosote
deposit.
• Leave the air control full open for about 5 min. every time you reload the stove to bring it back to proper
operating temperatures. The secondary combustion can only take place if the firebox is hot enough.
• Always check for creosote deposit once every two months and have your chimney cleaned at least once a
year.
If a chimney or creosote fire occurs, close all dampers immediately. Wait for the fire to go out and the heater to
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WARNING:
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