- 36 -
INST
ALLA
TION
- 36 -
INST
ALLA
TION
GENERAL REQUIREMENTS
Expansion vessel
The appliance has an integral sealed expan
-
sion vessel to accommodate the increase of
water volume when the system is heated.
Refer to Fig. 4.4 on page 31
for its techni-
cal data.
If the heating circuit has an unusually high
water content, calculate the total expansion
and add an additional sealed expansion
vessel with adequate capacity.
Mains water feed: central heating
There must be no direct connection to the
mains water supply even through a non re
-
turn valve, without the approval of the Local
Water Authority.
Filling
A method for initially filling the system and
replacing water lost during servicing must
be provided and it must comply with local
water authority regulations.
The correct method is shown in Fig. 5.4
.
The temporary connection must be re
-
moved immediately after filling.
Fig. 5.4
Temporary
connection
Control valve
Control valve
Double check valve
Supply pipe
(cold water inlet)
C.h. return pipe
The installer should ensure that no leaks ex
-
ist either inside the boiler or on the system
as frequent filling of the system could cause
premature scaling of the heat exchanger.
5.9 Water treatment
C.h. circuit
Where a new boiler is fitted to a new sys
-
tem with either plastic or copper pipes, it
is important the system is fully flushed, on
completion, to ensure flux residues, swarfs,
oils and other installation debris is removed.
Where a new boiler is fitted to an existing
system, it is important the debris from the
existing system is fully removed in order to
ensure the efficiency of the new appliance
is maintained.
Details on flushing procedure are given in
the
section "Initial filling of the system" to
page 52 of this manual.
5.10 Electrical supply
Warning, this appliance must be earthed.
External wiring to the appliance must be
carried out by a competent person and be in
accordance with the current I.E.E. Regula
-
tions and any local regulations which apply.
Reference should be made to the current
ETCI rules for electrical installations.
For Ireland (IE), refer to I.S.813.2002.
The boiler is supplied for connection to a
230 V~ 50 Hz supply. The supply must be
fused at 3A.
The method of connection to the electricity
supply must facilitate complete electrical
isolation of the appliance by the use of a
fused spur isolation switch. Its installation
permits a complete switching off in the con
-
ditions of the overvoltage category III. Alter
-
natively it can be used a 3A fused three pin
plug and unswitched shuttered socket outlet
both complying with BS 1363.
The point of connection to the electricity
supply must be readily accessible and adja
-
cent to the appliance, except where the ap
-
pliance is installed in a bathroom, this must
then be sited outside the bathroom.