2.1
STATUTORY REQUIREMENTS
THE GAS SAFETY (INSTALLATION AND USE) REGULATIONS
1994.
It is the law that all gas appliances are installed by a compe-
tent person, in accordance with the above regulations.
Failure to install appliances correctly could lead to prosecu-
tion. It is in your own interest, and that of safety, to ensure
that the law is complied with. In addition to the above regu-
lations, this appliance must be installed in accordance with
the current IEE Wiring Regulations, Local Building
Regulations, the Building Standards (Scotland) and bye laws
of the local water undertaking. It should also be in accor-
dance with the relevant recommendations in the current edi-
tions of the following British Standards and Codes of
Practice: BS5449, BS5546, BS5440:1, BS5440:2, BS6798,
BS6891, and BG.DM2
IMPORTANT NOTE:
manufacturer’s instructions must NOT be taken in any
way as over-riding statutory obligations.
2.2
BOILER POSITION
In siting the combination boiler, the following limitations
MUST be observed:
– the boiler is not suitable for external installation. The
position selected for installation should be within the
building, unless otherwise protected by a suitable enclo-
sure, and MUST allow adequate space for installation,
servicing, and operation of the appliance, and for air
ciculation around it (section 2.4);
– this position MUST allow for a suitable flue termination
to be made. The combination boiler must be installed
on a flat vertical wall which is capable of supporting
the weight of the appliance, and any ancillary equip-
ment;
– if the combination boiler is to be fitted in a timber fra-
med building it should be fitted in accordance with the
British Gas Publication Guide for Gas Installations In Tim-
ber Frame Housing, Reference DM2. If in doubt, advice
must be sought from the Local Gas Region;
– if the appliance is installed in a room containing a bath
or shower, any electrical switch or control utilising mains
electricity must be so situated that it cannot be touched
by a person using the bath or shower. Attention is
drawn to the requirements of the current I.E.E. Wiring
Regulations, and in Scotland the electrical provisions of
the Building Regulations applicable in Scotland;
– a compartment used to enclose the appliance MUST be
designed and constructed specifically for this purpose.
An existing cupboard, or compartment, may be used
provided it is modified accordingly;
– where installation will be in an unusual location, special
procedures may be necessary. BS6798 gives detailed gui-
dance on this aspect.
2.3
FLUE TERMINAL POSITION
Detailed recommendations for flue installation are given in
BS5440:1. The following notes are for general guidance:
– the boiler MUST be installed so that the terminal is
exposed to the external air;
– it is important that the position of the terminal allows
free passage of air across it at all times;
– it is ESSENTIAL TO ENSURE, in practice that products of
combustion discharging from the terminal cannot re-
enter the building, or any other adjacent building,
through ventilators, windows, doors, other sources of
natural air infiltration, or forced ventilation/air condi-
tioning. If this does occur, the appliance MUST be tur-
ned OFF IMMEDIATELY and the Local Gas Region con-
sulted;
– the minimum acceptable dimensions from the terminal
to obstructions and ventilation openings are specified
in fig. 3;
2
GENERAL REQUIREMENTS FOR INSTALLATION
Fig. 3
Directly below an openable
window, air vent or any other
ventilation opening
Below guttering, drain pipes or
soil pipes
Below eaves, balconies or
carport roof
From vertical drain pipes or soil
pipes
From internal or external
corners
Above adjacent ground, roof
or balcony level
From a surface facing
the terminal
From a terminal facing
the terminal
From an opening in the carport
(eg door, window into
dwelling)
Vertically from a terminal on
the same wall
Horizontally from a terminal on
the same wall
Adjacent to opening
A
B
C/D
E
F
G
H
I
J
K
L
M
300 mm
12 in
75 mm
3 in
200 mm
8 in
75 mm
3 in
300 mm
12 in
300 mm
12 in
600 mm
24 in
1,200 mm
48 in
1,200 mm
48 in
1,500 mm
60 in
300 mm
12 in
300 mm
12 in
Terminal position
Minimum spacing
TABLE 6
4