16
2000225065A
BOILER
DOMESTIC
WATER
HO
T OUT
COLD SUPPL
Y IN
DRAIN
POINT
'A'
FLOW CONTROL
VALVE
HEATING
CIRCUIT
RETURN
ADDITIONAL
EXPANSION
VESSEL
(if required)
Filling device
* BYPASS
(if required)
4 Heating System
Diagram 4.1
9168
The installation of the boiler must comply with the requirements
of the current issue of BS6798, in Ireland, refer also to the
current edition of I.S.813 "Domestic Gas Installations".
In GB it is necessary to comply with the Water Supply (Water
Fittings) Regulations 1999 (for Scotland, the Water Byelaws
2000, Scotland).
To comply with the Water regulations your attention is drawn to:
The Water Regulations guide published by the Water Regulations
Advisory Service (WRAS) gives full details of the requirements.
In IE the requirements given in the current edition of I.S.813
"Domestic Gas Installations" and the current Building Regulations
must be followed.
Diagram 4.2
11474
FILLING LOOP
TAP
FILLING LOOP TAP
EXTENSION
* Refer to section 11.6
4.5 Filling the Sealed System
The boiler has a built in filling loop, see diagram 4.2. To ease
access to the filling loop tap, push on the tap extension piece,
supplied in loose items pack, see diagram 4.2. Open the filling
loop tap to pressurise the system to 1 bar indicated on the digital
display with no demand.
Note that the electrical supply to the appliance has to be
switched on to enable the pressure to be read in the digital
display.
Refer to section 11.2 for filling procedure.
On filling the system a small amount of water maybe discharged
from the reduced pressure zone valve, see diagram4.2.
4.6 Water Treatment
In the case of an existing installation, it is ESSENTIAL that prior
to installing the new boiler the system is thoroughly flushed. For
optimum performance after installation of a new system, the
boiler and its associated central heating system should also be
flushed. Flushing should be carried out in accordance with
BS7593: 1992 using a cleanser such as Sentinel X300 or X400,
Fernox Superfloc or Salamander corrosion guard cleaner.
For long-term corrosion protection, after flushing, an inhibitor
suitable for stainless steel exchangers should be used, refer to
the current issue of BS 5449 and BS 7593 on the use of
inhibitors in central heating systems. Examples are Sentinel
X100 Fernox or Salamander corrosion guard inhibitor.
4.7 Draining Tap
A draining tap must be provided at the lowest points of the
system, which will allow the entire system to be drained.
A drain tap for the appliance is provided as an integral part of the
hydroblock, see diagram 12.11.
REDUCED
PRESSURE
ZONE VALVE
