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6.4 Using the fireplace with an open or a closed door
The fireplace can be used with an open or a closed door (Kalfire
w60/51f, w71/62f and w85/40f). when the door is open, the
heat output will fall to approximately 20% The wood consumption
will increase; as air has unregulated access to the wood.
The advantage is you have a cosy hearth fire.
The main difference between using the fireplace with an open
or a closed door is that each use has a different air requirement.
To optimally regulate the required air when using the fireplace
with an open door, the fireplace is equipped with a fresh air valve
(patented) at the rear.
The fresh air valve ensures that the air required to maintain
proper airflow is always used in the most efficient way when the
door is open. The valve redirects the fresh air into the room where
the fireplace is installed, so that it can be used optimally
for combustion. (see also section 5.1.1)
figure 33: open door
figure 34: Closed door
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