protected by a purpose designed guard. Terminal guards
are available from Quinnell, Barrett, and Quinnell, Old Kent
Road, London. State model C2, (G.C. Part No 382946).
– Where the terminal is fitted within 850 mm (34 in) of a
plastic or painted gutter, or 450 mm (18 in) of painted
eaves, an aluminium shield at least 1,500 mm (59 in) long
must be fitted to the underside of the painted surface.
– The air inlet/outlet flue duct MUST NOT be closer than
25 mm (1 in) to combustible material.
– In certain weather conditions the terminal may emit a
plume of steam. This is normal but positions where this
would cause a nuisance should be avoided.
2.4
VENTILATION REQUIREMENTS
Detailled recommendations for air supply are given in
BS5440:2. The following notes are for general guidance:
– It is not necessary to have a purpose provided air vent in the
room or internal space in which the appliance is installed.
2.5
GAS SUPPLY
– The gas supplier should be consulted at the installation
planning stage in order to establish the availability of an
adequate supply of gas.
– An existing service pipe MUST NOT be used without prior
consultation with the gas supplier.
– A gas meter can only be connected by the gas supplier or
their contractor.
– An existing meter should be of sufficient size to carry the
maximum boiler input plus the demand of any other
installed appliance. (BS6891: 1988).The gas required for
the boiler is specified in
Table 4.
– The governor at the meter must give a constant outlet
pressure of 20 mbar (8 inwg) for natural gas and 30 - 37
mbar (12 - 15 inwg) for LPG, when the appliance is running.
– The gas supply line should be purged.
NOTE: Before purging open all doors and windows, also
extinguish any cigarettes, pipes, and any other naked
lights.
– The complete installation must be tested for gas soundness.
– It is important to assure an adequate gas supply to the
appliance. No more than 3 m of 15 mm pipe should be
used. Where the supply exceeds 3 m the pipe should be
suitbly sized only reducing to 15 mm for the last 3 m prior
to the appliance.
2.6
ELECTRICITY SUPPLY
The appliance MUST be earthed. A mains supply of 230 V -
50 Hz single phase is required. All external controls and
wiring MUST be suitable for mains voltage.
Wiring should be in 3 core PVC insulated cable NOT LESS
than 0.75 mm
2
(24 x 0.2 mm) to BS6500, Table 16. Wiring
external to the boiler MUST be in accordance with current
l.E.E. Wiring Regulations (BS 7671) and local regulations. The
supply connection to the flying lead provided MUST be made
to a fused double pole switch, having a 3 mm (1/8 in) contact
separation in both poles, serving only the boiler and system
controls. The fuse rating should be as per the original instruc-
tions. This connection should be readily accessible and be
made adjacent to the boiler (except in the case of bathroom
installations for domestic boilers where the point of connec-
tion to the mains MUST be outside of the bathroom).
2.7
EXTERNAL CONTROLS (Refer to section 3.10)
The boiler is intended for use with a 240 V room thermostat.
The connection is made inside the control box as described in
section 3.10.
2.8
WATER SYSTEMS - GENERAL
– This appliance is designed for connection to sealed cen-
tral heating water systems.
– Check that the mains water pressure is sufficient to pro-
duce the required D.H.W. flow rate, but does not exceed
the maximum D.H.W. pressure (
Table 4). If necessary, a
pressure reducing valve must be fitted to the mains sup-
ply before the D.H.W. inlet connection.
2.9
REQUIREMENTS FOR SEALED WATER SYSTEMS
The heating system design should be based on the following
information:
a) The available pump head is given in fig. 4.
b) A minimum flow rate corresponding to a heating differen-
tial of 11°C must be obtained at all times.
c)
A heating by-pass is usually only required when micro-
bore piping is used on the system.
If however condition
(b) can not be satisfied a heating by-pass should be fitted.
If thermostatic radiator valves are to be installed, at least
one radiator should be without a thermostatic valve (usu-
ally the bathroom radiator).
d) A sealed system must only be filled by a competent per-
son using one of the approved methods shown in fig. 6.
The system design should incorporate the connections
appropriate to one of these methods.
e) The following paragraphs outline the specifications of the
items fitted to the boiler.
5
0
200
1600
1400
1200
1000
800
600
400
PORTATA (l/h)
PREV
ALENZA RESIDU
A (mbar)
500
400
100
200
300
30
25
KEY
1
Available Head for
“80 C”
model
2
Available Head for
“100 C”
model
Flow rate (l/sec)
A
vailable
head
(mbar)
Fig. 4
1
2
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