Hanwood - Manual
4
access for rodents. In extreme cases the placement
of the terminal on the external wall may pose prob-
lems and remedial action may be required to relo-
cate the terminal or provide two terminals on oppo-
site walls to balance the wind effect.
Where the stove is connected to outside air and
there is no draught stabiliser fitted there is no
requirement for an additional air supply, provided a
successful ‘smoke draw test’ has been carried out
as part of commissioning.
Where no outside air duct is fitted please refer to
Building Regulations Part J to determine the size of
permanent air vent required, as follows:
Install where draft stabilizer is fitted:
Permanently open vents as below:
If design air permeability >5.0m3/(h.m2) then
300mm2/kW for first 5kW of appliance rated output
850mm2/kW for balance of appliance rated output
If design air permeability <5.0m3/(h.m2) then
850mm2/kW of appliance rated output (4)
Install where no draft stabilizer is fitted:
Permanently open vents as below:
If design air permeability >5.0m3/(h.m2) then
550mm2/kW of appliance rated output above 5kW
If design air permeability <5.0m3/(h.m2) then
550mm2 per kW of appliance rated output (4)
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.
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. Air
inlet grills should be positioned so they do not
become liable to blockage.
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
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 communi-
cate 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 mois-
ture. Existing air vents should be of the correct
size and unobstructed for the appliance in use.
If there is anextraction fan fitted in adjacent
rooms where this appliance is fitted, additional
air vents may be required to alleviate the possi-
bility of spillage of products 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.
Note:- If there is any work that is being carried
out that would effect the air quality supplied to
the stove such as sanding a floor or glueing
linoleum etc. the stove must be out of operation.
The dust or vapours may be a potential hazard,
the air supply and local area needs to be thor-
oughly ventilated before putting the stove in
operation again.
Air vents in internal walls should not communi-
cate 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 mois-
ture.
Existing air vents should be of the correct size
and unobstructed for the appliance in use. If
there is an extraction fan fitted in adjacent
rooms where this appliance is fitted, additional
air vents may be required to alleviate the possi-
bility of spillage of products of combustion from
the appliance/flue while the fan is in operation.
Refer to B.S. 8303 Part 1.