Down Draughts; Ventilation & Combustion Air Requirements; Permanent Air Vent - Stanley Aoife Installation And Operating Instructions Manual

DOWN DRAUGHTS

However well designed constructed and positioned,
the satisfactory performance of the flue can be
adversely affected by down draught caused by near-
by hills, adjacent tall buildings or trees. These can
deflect wind to blow directly down the flue or create
a zone of low pressure over the terminal.
A suitable terminal or cowl will usually effectively
combat direct down blow but no cowl is likely to pre-
vent down draught due to a low pressure zone.
(See Fig.4)
Direction of wind
Pressure zone
Direction of wind
Pressure zone
Direction of wind
Pressure zone
VENTILATION AND COMBUSTION AIR
REQUIREMENTS
The minimum effective air requirement for this appli-
ance is 13cm 2 . When calculating combustion air
requirements for this appliance use the following
equation: 550mm 2 per each kW of rated output
above 5 kW should be provided, where a flue
draught stabiliser is used the total free area shall be
2
increased by 300mm
If there is another appliance using air fitted in the
same or adjacent room, it will be necessary to pro-
vide an additional air supply.
Suction zone
Suction zone
Suction zone
for each kW of rated output.
All materials used in the manufacture of air vents
should be such that the vent is dimensionally stable,
corrosion resistant, and no provision for closure.
The effective free area of any vent should be ascer-
tained before installation. The effect of any grills
should be allowed for when determining the effective
free area of any vent.
Air vents direct to the outside of the building should
be located so that any air current produced will not
pass through normally occupied areas of the room.
An air vent outside the building should not be locat-
ed less than the dimensions specified within the
Fig.4
Building Regulations and B.S. 8303: Part 1 from
any part of any flue terminal. These air vents must
also be satisfactorily fire proofed as per Building
Regulations and B.S. 8303: Part 1.
Air vents in internal walls should not communicate
with bedrooms, bedsits, toilets, bathrooms or rooms
containing a shower.
Air vents traversing cavity walls should include a
continuous duct across the cavity. The duct should
be installed in such a manner as not to impair the
weather resistance of the cavity.
Joints between air vents and outside walls should be
sealed to prevent the ingress of moisture. Existing
air vents should be of the correct size and unob-
structed for the appliance in use.
extraction fan fitted in adjacent rooms where this
appliance is fitted, additional air vents may be
required to eleviate the possibility of spillage of prod-
ucts of combustion from the appliance/flue while the
fan is in operation. Refer to B.S. 8303 Part 1.
Where such an installation exists, a test for spillage
should be made with the fan or fans and other
appliances using air in operation at full rate, (i.e.
extraction fans, tumble dryers) with all external
doors and windows closed.
If spillage occurs following the above operation, an
additional air vent of sufficient size to prevent this
occurrence should be installed.

PERMANENT AIR VENT

The stove requires an adequate air supply in order
for it to operate safely and efficiently. The installer
may have fitted a permanent air supply vent into the
room in which the stove is installed to provide com-
bustion and/or ventilation air. This air vent should
not under any circumstances be shut off or sealed.
Extractor Fan
There must not be an extractor fan fitted in the same
room as the stove as this can cause the stove to
emit smoke and fumes into the room.
5
If there is an