Technical data

6 720 611 445 GB (04.05)
12
Installation
Some plastics are permeable to oxygen and must be
avoided, a pipe with a polymer barrier should be used.
Sealed System
A sealed system must include an expansion vessel,
pressure gauge and pressure relief valve set to operate
at 3 bar - these are available as proprietary kits. The
expansion vessel and fittings must be connected at the
neutral point of the system on the entry to the pump.
Suitable pump and diverter valves are also required.
Refer to Fig. 5 & Fig. 6. The sealed system must be filled
through a WRAS approved filling kit. Refer to Fig. 7.
The appliance must not be operated without the system
being full of water and correctly pressurised.
All connections in the system must be able to withstand
a pressure up to 3 bar. The system and appliance must
be properly vented. Repeated venting loses water from
the system and usually indicates a leak. A drain cock to
BS 2879 must be fitted to the lowest point on the sys-
tem.
No galvanised radiators or pipes must be used.
If any system water treatment is required then only
products suitable for use with Aluminium shall be used
i.e Fernox- Copal or Super concentrate or Sentinal
X100, in accordance with the manufacturers instruc-
tions. The use of any other substances will invalidate
the guarantee. The pH value of the system water must
be less than 8 or the appliance guarantee will be invali-
dated.
Suitable products are available from Betz-Dearborn Tel:
0151-4209563 and Fernox Tel: [phone].
IMPORTANT: Check that no dirt is left in the water
pipe work as this could damage the appliance. Thor-
oughly flush the heating system and the mains water
supply before fitting the appliance to the wall in accord-
ance with the recommendations of BS7593:1992.
Domestic Hot Water
The appliance is NOT suitable for direct water
supply.
Do not connect to a direct cylinder.
The appliance can be connected to any indirect cylin-
der i.e. unvented or thermal store to realise the benefits
from a “dry loft”. For more information contact Worces-
ter Heat Systems Helpline 08705 266241.
Note: Indirect coil type cylinders with an immersion cal-
orifier suitable for a pressure of 0.35 bar above the set-
ting of the pressure relief valve may be used. Single
feed indirect cylinders are not suitable for sealed
systems. Any connection to the mains water supply
must conform to the relevant Buildings and Water Reg-
ulations and be approved by the local water company.
Fig. 5
FEED & VENT
CISTERN
S.H
.
S.H.
S.H. MINIMUM ST
ATIC HEAD 1.0m MEASURED
FROM THE HIGH EST POINT IN THE HEATING
SYSTEM (TOP SURFACE OF THE APPLIANCE
OR HIGHEST POINT IN THE HEATING
SYSTEM) TO THE WATER LEVEL IN THE FEED
AND EXPANSION TANK.
DIVE
RTER
VALVE
DOMESTIC
HOT WATER
CYLINDER
BOILER
RADIATOR
RADIATORRADIATOR
TYPICAL OPEN VENTED SYSTEM
PUMP
DRAIN
COCK
RADIATOR
PRIMARY
COLD FEED
Minimum
diameter
15mm
.
HEATING
VENT
Minimum
diameter
22mm.
150mm
max.
6 720 611 445-04.1O