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• When the unit is used in extraction mode, a sufficiently large
ventilation hole must be provided, with dimensions that are approxi-
mately the same as the outlet hole.
• National and regional building regulations impose a number of
restrictions on using hoods and fuel-burning appliances connected to
a chimney, such as coal or oil room-heaters and gas fires, in the
same room.
• Hoods can only be used safely with appliances connected to a
chimney if the room and/or flat (air/environment combination) is
ventilated from outside using a suitable ventilation hole approximately
500-600 cm
2
large to avoid the possibility of a depression being
created during operation of the hood.
• If you have any doubts, contact the relevant controlling authority or
building inspector’s office.
• Since the rule for rooms with fuel burning appliances is “outlet hole of
the same size as the ventilation hole”, a hole of 500-600 cm
2
, which
is to say a larger hole, could reduce the performance of the extractor
hood.
• If the hood is used in its recirculation mode, it will operate simply
and safely in the above conditions without the need for any of the
aforementioned measures.
• When the hood is used in its recirculation mode, the following rules
must be followed to obtain optimal operation:
The ducting must be fire retardant, 120mm in diameter and the
length should be no more than:
3 metres with one 90 degree bend
2 metres with two 90 degree bends
Bends of more than 90 degrees will reduce the efficiency of the hood
and reduce the airflow.
• Failure to observe these basic instructions will drastically reduce the
performance and increase the noise levels of the extractor hood.
Summary of Contents for DD 8765
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