Supplied By www.heating spares.co Tel. 0161 620 6677
6
Fig. 5
If installed less than 2m above a pavement or
platform to which people have access (including
balconies or flat roofs) the terminal must be
protected by a guard of durable material. The
guard must be fitted centrally over the terminal.
Refer to BS 5440 Part 1, when the terminal is 0,5
metres (or less) below plastic guttering or 1 metre
(or less) below painted eaves.
3.5
AIR SUPPLY
The following notes are intended for general guidance
only.
This appliance is a room sealed, fan-flued boiler,
consequently it does not require a permanent air vent
for combustion air supply.
When installed in a cupboard or compartment, venti-
lation for cooling purposes is also not required.
3.6
WATER CIRCULATION
Detailed recommendations are given in BS 5449
Part 1 and BS 6798. The following notes are for
general guidance only.
3.6.1
PIPEWORK
It is recommended that copper tubing to BS 2871 Part
1 is used in conjunction with soldered capillary joints.
Where possible pipes should have a gradient to
ensure air is carried naturally to air release points
and that water flows naturally to drain cocks.
Except where providing useful heat, pipes should
be insulated to avoid heat loss and in particular to
avoid the possibility of freezing. Particular atten-
tion should be paid to pipes passing through
ventilated areas such as under floors, loft-space,
and void areas.
3.6.2
AUTOMATIC BY-PASS
The appliance has a built-in automatic by-pass,
consequently there is no requirement for an ex-
ternal by-pass, however the design of the system
should be such that it prevents boiler ‘cycling’.
3.6.3
DRAIN COCKS
These must be located in accessible positions to
facilitate draining of the appliance and all water pipes
connected to the appliance. The drain cocks must be
manufactured in accordance with BS 2879.
3.6.4
AIR RELEASE POINTS
These must be positioned at the highest points in
the system where air is likely to be trapped. They
should be used to expel trapped air and allow
complete filling of the system.
3.6.5
EXPANSION VESSEL
The appliance has an integral expansion vessel to
accommodate the increased volume of water when
the system is heated. It can accept up to 8 litres of
expansion from within the system, generally this is
sufficient, however if the system has an unusually high
water content, it may be necessary to provide additional
expansion capacity (see 6.19).
Fig. 5 A
3.6.6
FILLING POINT
A method for initial filling of the system and
replacing water lost during servicing etc. must be
provided. This method of filling must comply with
the local water authority regulations.
Fig. 5 shows a widely accepted method.
3.6.7
LOW PRESSURE SEALED SYSTEM
An alternative method of filling the system would
be from an independent make-up vessel or tank
mounted in a position at least 1 metre above the
highest point in the system and at least 5 metres
above the boiler (see fig. 5 A). The cold feed from
the make-up vessel or tank must be fitted with an
approved non-return valve and stopcock for iso-
lation purposes. The feed pipe should be con-
nected to the return pipe as close to the boiler as
possible.
3.6.8
FREQUENT FILLING
Frequent filling or venting of the system may be
indicative of a leak. Care should be taken during
the installation of the appliance to ensure all
aspects of the system are capable of withstand-
ing pressures up to at least 3 bar.
Make-up vessel
or tank
Automatic
air-vent
Non-return
valve
Stopcock
5.0 metres minimum
Heating
return