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FAQS
8) What is draft?
Draft is the ability of the chimney to exhaust by-products produced during the normal combustion process.
9) What can cause a poor draft?
The most common factors for poor draft are:
a. Atmospheric pressure and air supply
b. Environmental
condition
c. Cold chimney temperature
d. Poor chimney installation and maintenance
a)
Atmospheric Pressure and Air Supply
Atmospheric pressure affecting the draft from a chimney can be either outside the home, inside the home or both.
Outside the home, a high-pressure day (clear and cool) generally creates a better draft in the chimney than a low-pressure
day (overcast and damp). Inside the home normal household appliances, such as clothes dryers and forced air furnaces
compete for air, resulting in inadequate amounts of air available to fuel a
fi
re and create a condition known as negative
pressure. Under extreme conditions of negative pressure the combustion by-products can be drawn from the chimney
into the house. This condition is commonly referred to as down drafting.
There are several factors that impact the amount of air available in the home. Increased amounts of insulation, vinyl
windows, extra caulking in various places and door seals can all keep heat in but may also make a home too airtight.
If you are in doubt about whether or not there is suf
fi
cient air in your home for your stove, curtail from using those
appliances known to consume the air where possible, or open a window or door to allow air to enter the home.
b)
Environmental Conditions
High trees, low lying house location such as in a valley, tall buildings or structures surrounding your house and windy
conditions can cause poor draft or down drafting.
c)
Cold Chimney Temperature
Avoid cold chimney temperatures by burning a hot
fi
re for the
fi
rst
fi
fteen to forty minutes, being careful not to over
fi
re. If any part of the chimney or parts of the stove start to glow, you are over
fi
ring the stove. Where possible, install a
temperature gauge on the chimney so temperature drops can be seen.
d)
Chimney Installation and Maintenance
Avoid using too many elbows or long horizontal runs. If in doubt, contact a chimney expert and/or chimney
manufacturer for help. Clean chimney, rain caps and especially spark arrester regularly, to prevent creosote build-up,
which will signi
fi
cantly reduce chimney draw and possibly a chimney
fi
re.
11. Should I close or open the air control fully when shutting down the stove?
Just before shutting down the stove, run on high for a few minutes. This allows the chimney temperatures to remain as high as
possible for as long as possible. Cold chimney temperatures create creosote.
Note: This sheet is intended as an aid and does not supersede any local, provincial or state requirements. Check with of
fi
cials or
authorities having jurisdiction in your area.
