Air Supply - andrews HIflo EVO HF 30/300 Installation And Service Manual

3.4

Air Supply

Position of Air Vents
High Level
Low Level
Not permitted for installations exceeding 70kW
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Issue 4 21042918
Air from room or internal space
10cm 2 per kW*
20cm 2 per kW*
See
Detailed recommendations for air supply are given in BS
5440 part 2 and BS6644 for installations exceeding
70kW.
The following notes are intended to give general guidance:
Where the heater is to be installed in a room or internal space
the heater requires the room or internal space containing it to
have a permanent air vent. The vent must be direct to outside
air
Where the heater is to be installed in a compartment, permanent
air vents are required in the compartment at high and low level.
These air vents must either communicate with a room or internal
space or be direct to outside air.
The minimum effective areas of the permanent air vents
required are as follows:-
Air Vent Areas
Air direct from outside
5cm 2 per kW
10cm 2
Note
Both air vents must communicate with the same room or
internal space or must both be on the same wall to
outside air.
Where compartment air vents are open to a room or internal
space, the room or internal space must itself have a permanent
air vent(s) as previously specified.
For multiple installations where the total heat input exceeds 70
kW reference must be made to BS 6644. The table on p7 should
be used to calculate requirements. Detailed recommendations
are given in BS 6644 Clause 19.
The following notes are intended to give general guidance.
Ventilation shall prevent the heater environment from exceeding
32°C.
The purpose provided space housing the heater(s) must have
permanent air vents communicating directly with the outside air,
at high and low level. Where communication with the outside air
is possible only by means of high level air vents, ducting down
to floor level for the lower vents should be used.
For an exposed building, air vents should be fitted preferable on
all four sides, but on at least two sides.
Air vents should have negligible resistance and must not be
sited in any position where they are likely to be easily blocked or
flooded or in any position adjacent to an extraction system which
is carrying flammable vapour or other contaminated air.
per kW
12