201
8
Installation Details
Location of Boiler
The installation of the 201 must be on a suitable non-combustible load bearing wall which will
provide an adequate fixing for the boiler mounting bracket assembly. A satisfactory flue with a minimum of
600mm (2 ft.) rising vertically above thedraught diverter must also be provided,terminating in a British Gas
Approved cowl.
The location must also provide adequate room for servicing.
The location must also be provided with an adequate air supply for combustion purposes. The boiler must
not be installed in a room containing a bath or shower, or in a bedroom or bed-sitting room. In installations
of an unusual location, special procedures are necessary and BS 6798 gives detailed guidance on this
aspect. The location should be as centralised as possible with the water piping system and in an area not
subjected to frost conditions.
Flue system
DetailedrecommendationsforfluearegiveninBS5440Part.1.Thefollowingnotesareintendedforgeneral
guidance. The cross sectional area of flue serving the boiler must not be less than the area of the flue outlet
of the appliance.
The flue should terminate in accordance with BS 5440 Part 1. The boiler has a flue spigot designed for
aluminium or stainless steel flue pipe. If double walled flue pipe is used, it should be of a type accepted by
BritishGas.Alwaysuseasplitfluecliporflangedjointabovethefluedivertertoallowtheremovaloftheboiler.
A vertically rising flue above the diverter for a minimum length of 600 mm (2 ft.) is required before any bend
isfitted,whichshouldnotbea90°pattern.Thefluepipemustbeadequatelysupportedandnotbeincontact
with any inflammable material.
If any existing chimney is to be used, it should be lined with a stainless steel flexible liner or any other liner
acceptable to British Gas. (Chimneys lined with salt glazed earthenware pipes are acceptable if the pipes
conform to BS 65.). The number of metal flue liner joints should be kept to the minimum for connecting the
boiler to an existing flue, the flue must be clean of any soot or loose material. Dampers must be removed.
Theflueshouldbe,asfarasispractical,verticallyrisingwiththeavoidanceofhorizontalruns.Themetalflue
pipe listed above should form the initial connection from the boiler to the existing chimney (and liner). Refer
to page 12 if an extraction fan is fitted in the area.
Air supply
Detailedrecommendationsaregivenin BS 5440 Part. 2. The following notes are intended to give guidance.
Room or internal air space supply:
The 201 requires a permanent air vent for combustion air either from the room direct to outside air
ortoanadjacentroomwhichmustitselfhaveapermanentairventofthesamesize,directtooutsideair.The
minimum size of this air vent must be: 94 cm2free a (14 in2). A proprietry air vent may be marked with its
effectivefreearea,ifnot,thisinfor-mationcanusuallybesuppliedbythemaker.Theventshouldbedesigned
to diffuse the air in windy conditions and should be sited to reduce room draughts, i.e. at top level. The
aperture in the vent should not pass preferably, a 10 mm (318 in.) ball but allow the entry of a 5 mm (3116
in.) ball. (Additional gauzes or screens should not be used).
Existing air vents should be taken into account when assessing air vent requirements. An air vent in an
internalwallshouldnotcommunicatewithabedroom,toilet,bathroomorkitchenandshouldnotbemorethan
450 mm (18 in.) above floor level in order to reduce the spread of smoke in the event of a fire. An air vent
directtooutsideairmustnotbeloca-tedlessthan600mm(2ft.)awayfromanypartofanopenfluedterminal.
