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9.
What can cause a poor draft?
There are several common factors that can contribute to poor draft:
A.
Atmospheric Pressure and Air Supply
Atmospheric pressure affecting the draft from a chimney can be outside the home,
inside the home, or both. Outside the home, a high-pressure (clear and cool) day
generally creates a better draft in the chimney than a low-pressure (overcast and damp)
day. Inside the home, household appliances, such as forced-air furnaces or clothes
dryers, compete for air, often resulting in inadequate amounts of air available to fuel a fire
and creating a condition known as negative pressure. Extreme conditions of negative
pressure can cause the combustion by-products to be drawn from the chimney and into the
house. This condition is commonly known as “down drafting.”
There are several factors that can affect 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 as to
whether or not there is sufficient air in your home for your stove, refrain from using those
appliances known to consume air when possible, or open a door or a window to allow
some air to enter the home.
B.
Environmental Conditions
High trees, a low-lying house location (such as in a valley), tall buildings or structures
surrounding your house and even windy conditions can cause pool draft or down drafting.
C.
Cold Chimney Temperature
Avoid cold chimney temperatures by burning a hot fire for the first fifteen to forty minutes
after building a fire, being careful not to over-fire. If any part of the chimney or parts of the
stove start to glow, you are over-firing 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 your chimney, rain cap(s) and
especially the spark arrester regularly, in order to prevent creosote build-up – which can
significantly reduce chimney draw and possibly create a chimney fire.
10.
Should I close or open the air control fully when shutting down the stove?
When shutting down the stove, fully open the air control. This will allow chimney
temperatures to remain as high as possible for as long as possible. Remember, cold
chimney temperatures create creosote.
NOTE: This section is intended as an aid and does not supersede any local, state or
like requirements.
Check with officials or authorities having jurisdiction in your area.
