Solution 2.5-ZC Fireplace Installation and Operation Manual
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8.10.1 Air Supply in Conventional Houses
The safest and most reliable supply of combustion air for your wood fireplace is from the
room in which it is installed. Room air is already preheated so it will not chill the fire, and its
availability is not affected by wind pressures on the house. Contrary to commonly
expressed concerns, almost all tightly-sealed new houses have enough natural leakage to
provide the small amount of air needed by the fireplace. The only case in which the wood
fireplace may not have adequate access to combustion air is if the operation of a powerful
exhaust device (such as a kitchen range exhaust) causes the pressure in the house to
become negative relative to outdoors.
If you do install an air supply through the wall of the house, be aware that its pressure can
be affected during windy weather. If you notice changes in wood fireplace performance in
windy weather, and in particular if smoke puffs from the fireplace, you should disconnect
the outdoor air duct from the fireplace and remove the duct. In some windy conditions,
negative pressure at the duct weatherhood outside the house wall may draw hot exhaust
gases from the fireplace backwards through the duct to outdoors. Check the outdoor air
duct for soot deposits when the full system is cleaned and inspected at least once each
year.
