Detailed recommendations for air supply are given in
the current Building Regulations J1/4/5.
The following notes are intended to give general
guidance:-
Kitchen or Internal Air Supply
Wherever a flue appliance is to be installed, it must
have a permanent air vent. This vent must be either
direct to outside air or to an adjacent room or internal
space which must itself have a permanent air vent of at
least the same size direct to outside air. The minimum
effective area of the permanent air vent in the outside
wall must be 30.5cm
2
(4.75in
2
).
Effect of Extractor Fan
Avoid if possible the installation of an extractor fan in
the same room as the appliance or the room where the
permanent air vent is located. Additional air inlets must
be fitted to introduce compensating air, equivalent to
the capacity of the fan when fitted.
Hot water systems should be in accordance with the
relevant recommendations given in BS. 6700.
The following notes are of particular importance.
1. In domestic hot water systems the hot water
storage vessel must be of the indirect cylinder of
calorific type.
2. The hot water storage vessel should be insulated,
preferably with not less than 75mm thick mineral
fibre, or its equivalent.
3. Pipework should be insulated to help prevent heat
loss and possible freezing, particularly where pipes
are run through roof spaces. Cisterns situated in area
which may be exposed to freezing conditions should
also be insulated.
4. Draining taps must be located in accessible positions
which permit the draining of the appliance and hot
water storage vessel. Draining taps should be at
least 1/2in BSP nominal size and be in accordance
with BS. 2879.
5. The appliance boiler section should be connected to
a cistern water supply, subject to a maximum head
of 18.25m (1.8 bar).
6. Water carrying copper tubes should be to BS. 2871,
Part 1.
7. Hot water systems should be in accordance with the
relevant recommendations given in BS. 6700.
8. The use of horizontal pipe runs should be avoided
wherever possible in order to prevent the collection
of air in the system. If horizontal runs are unavoided
the pipes should rise upwards in the direction away
from the appliance.
Hot Water Storage Vessel
It is recommended that an indirect 140 litre (30 gallon)
hot water storage cylinder of the double feed type e.g.
(Manufactured by Albion Cylinders) complying with the
BS. 1566, should be insulated, preferably with not less
than 75mm thick mineral fibre or its equivalent, and
fixed vertically as near as possible to the appliance.
The water draw-off pipes to the taps must be dead leg
connection from the vent expansion pipe. A drain tap
must be fitted at the lowest point of the system.
A towel rail of not more than 0.5mm
2
heating surface
may be heated providing the flow and return pipes are
not more than 5m each in length, and provided the
cylinder and pipes to the cylinder are insulated.
If the cylinder is very close to the cooker, a towel rail is
advisable as a heat leak and lagging should not be
applied.
NOTE:
The appliance must not be operated if the water
system is out of operation, or has been drained.
Corrosion Inhibitor
A corrosion inhibitor can be used when installing this
appliance to an
Indirect Hot Water Cylinder Only
.
The combined appliance is floor-mounted and the
space in which the appliance is to be fitted must have
the following minimum dimensions:-
Width:
1145mm
Depth:
1575mm
Height:
1320mm
This space includes the following minimum clearances
for servicing:-
Between wall and L.H. side of appliance
300mm
Between wall and R.H. side of appliance
Zero
Above the raised insulating cover handle
75mm
In addition, adequate clearance must be available at the
front of the appliance to enable it to be operated and
serviced.
Flue pipes and fitting must not be closer than 25mm to
combustible materials and where passing through a
combustible partition such as a ceiling or roof, must be
enclosed in non-combustible sleeve providing an air
Installation Instructions
AIR SUPPLY
HOT WATER SYSTEM
4
Fig.3 Typical Gravity System
INSTALLATION OF APPLIANCE -
GENERAL