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4A.4 FLUE SYSTEM
The terminal should be located where the dispersal of combustion
products is not impeded and with due regard for the damage
and discoloration that may occur to building products located
nearby. The terminal must not be located in a place where it is
likely to cause a nuisance (see I.S. 813).
In cold and/or humid weather, water vapour will condense
on leaving the terminal; the effect of such pluming must be
considered.
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
I.S. 813, when the terminal is 0.5 metres (or less) below plastic
guttering or 1 metre (or less) below painted eaves.
4A.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, ventilation for
cooling purposes is also not required.
4A.6 WATER CIRCULATION
Specific recommendations are given in I.S. 813. The following
notes are for general guidance only.
4A.6.1 PIPEWORK
It is recommended that copper tubing be 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 attention should be paid to pipes passing
through ventilated areas such as under floors, loft space, and
void areas.
4A.6.2 AUTOMATIC BY-PASS
The appliance has a built-in automatic by-pass, consequently
there is no requirement for an external by-pass, however the
design of the system should be such that it prevents boiler
‘cycling’.
4A.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.
4A.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
.
4A.6.5 EXPANSION VESSEL
The appliance has an integral expansion vessel to accommodate
the increased volume of water when the system is heated.
Refer to the specification table for more detailed information
.
4A.6.6 FILLING POINT
A method for initial filling of the system and replacing water
lost during servicing etc. should be provided (see fig. 6). You
should ensure this method of filling complies with the local water
authority regulations.
4A.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. 7
). The cold feed from
the make-up vessel or tank must be fitted with an approved
non-return valve and stopcock for isolation purposes. The feed
pipe should be connected to the return pipe as close to the
boiler as possible.
4A.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
withstanding pressures up to at least 3 bar.
4A.7 ELECTRICAL SUPPLY
The appliance is supplied for operation on 230V @ 50Hz electrical
supply; it must be protected with a 3-amp fuse (supplied). The
method of connection to the mains electricity supply must allow
for complete isolation from the supply. The preferred method is
by using a double-pole switch with a contact separation of at
least 3mm. The switch must only supply the appliance and its
corresponding controls, i.e. time clock, room thermostat, etc.
Alternatively an un-switched shuttered socket with a fused 3-pin
plug both complying with BS 1363 is acceptable.
Warning!
This appliance must be earthed.
4A.8 MOUNTING ON A COMBUSTIBLE
SURFACE
The appliance can be mounted on a wall of combustible material
without any requirement to fit any additional protective (fire-
resistant) material.
4A.9 TIMBER FRAMED BUILDINGS
I
f the appliance is to be fitted in a timber framed building, it
should be fitted in accordance with I.S. 813 and local Building
Regulations.
The Institute of Gas Engineers publication (IGE/UP/7) ‘Guide
for Gas Installations in Timber Frame Buildings’ gives specific
advice on this type of installation.
4A.10 WATER TREATMENT
Vokera recommend that water treatment be carried out in
accordance with the Benchmark Guidance on water treatment
in central heating systems. If water treatment products
are to be used, then they must be entirely suitable for use
with a stainless steel heat exchanger. Any water treatment
product, must be administered in strict accordance with the
manufacturer’s instructions.
If the appliance is to be installed to an existing system; water
treatment and flushing of the complete heating system should
be carried out in accordance with BS 7593 and the Benchmark
Guidance on water treatment in central heating systems.
4A.11 DECLARATION OF CONFORMITY
A Declaration of Conformity (as defined in I.S. 813) must be
provided on completion of the installation.
A copy of the declaration must be given to the responsible
person and also to the gas supplier if required.
