Mains Supply; Electricity Supply; Gas Supply; Water Supply - Worcester GREENSTAR 24i Junior Installation, Commissioning And Servicing Instructions

PRE-INSTALLATION
INHIBITOR
Add a suitable inhibitor or combined inhibitor/anti-freeze, if the system
is exposed to freezing conditions, to the heating system in accordance
with the DWTA code of practice and manufacturer's guidelines.
WARNING: Sealing agents
▶ Normally the addition of sealing agents to the system
water is not permitted as this can cause problems
with deposits left in the heat exchanger.
▶ In cases where all attempts to find a micro leak have
failed, Worcester, Bosch Group supports the use of
Fernox F4 leak sealer.
WATER TREATMENT PRODUCTS
Suitable water treatment products can be obtain from the following
manufacturers:
FERNOX 0870 601 5000 or www.fernox.com
SENTINEL 0800 389 4670 or www.sentinel-solutions.net
ARTIFICIALLY SOFTENED WATER
It is possible to have an ion exchange water softener fitted to the cold
water system of the property. However, the boiler requires an untreated
cold water connection taken from the mains supply, before the water
softener, to the primary water filling point of the heating system.
Alternatively there are water softening/treatment devices that do not
adjust or alter the pH levels of the water. With these devices it may not
be necessary to provide an untreated water by-pass to the primary water
filling point of the heat system.
3.2

MAINS SUPPLY

3.2.1 ELECTRICITY SUPPLY

• Supply: 230V - 50 Hz, 140 Watts
• Cable: PVC insulated 0.75mm
• External 3A fuse to BS1362.
• The appliance must be earthed.
• This appliance must not be connected to a three phase supply.
• IPX4D.
NOTICE: This is reduced to IP20 if the following
mechanical timers are fitted;
7 716 192 036 or 7 716 192 037 or FW100 controller
7 716 192 067.
• Wiring must comply with the latest edition of BS7671 (IEE wiring
regulations).

3.2.2 GAS SUPPLY

• Boilers using Natural Gas (NG) must be connected to a governed
meter.
• Liquid Petroleum Gas (LPG) must be connected to a regulator.
• Installation and connection of the gas supply to the boiler must be in
accordance with BS6891.
• Under no circumstance should be size of the gas supply pipe be less
than 22mm.
• The meter or regulator and pipe work to the meter must be checked,
preferably by the gas supplier.
This is to ensure that the equipment is in good working order and can
meet the gas flow and pressure requirements, in addition to the
demand from any other appliance being served.
10
2
(24 x 0.2mm) rated to 90 °C.

3.2.3 WATER SUPPLY

WATER MAINS PRESSURE:
• Minimum mains water pressure: 1.3 bar for 24 and 28i Junior, for
maximum performance.
• Maximum mains fed water pressure 10 bar.
If necessary fit a pressure reducing valve.
NOTICE: Non-return, flow back prevention devices
(including those associated with water meters) fitted to
the mains water supply can cause a pressure build up
which could damage the boiler and other household
appliances.
• Where the mains water supply has a non-return, flow back prevention
valve fitted, a mini expansion vessel (1) should be connected to the
mains water inlet pipe (2) between the non-return valve (3) and the
boiler (4) as shown below.
1
2 3
1 Mini expansion vessel - part no. 7 716 102 105
2 Mains water inlet pipe
3 Non return valve
4 Boiler
USE IN HARD WATER AREAS:
Normally there is no need for water treatment to prevent scale formation
as the maximum temperature of the HW heat exchanger is limited by the
electronic control.
In areas where temporary water hardness exceeds 200 ppm,
consideration may need to be given to the fitting of a scale prevention
device. In such circumstances, the advice of the local water authority
should be sought.
3.3

WATER SYSTEMS AND PIPE WORK

PLASTIC PIPE WORK:
• Any plastic pipe work must have a polymeric barrier with 600mm
(minimum) length of copper pipe connected to the boiler.
• Plastic pipe work used for underfloor heating must be correctly
controlled with a thermostatic blending valve limiting the temperature
of the circuits to approximately 50 °C.
PRIMARY SYSTEMS CONNECTIONS/VALVES:
• All system connections, taps and mixing valves must be capable of
sustaining a pressure up to 3 bar.
• Radiator valves should conform to BS2767:10.
• All other valves should conform to BS1010.
• Thermostatic radiator valves (TRV's) must be used on all radiators
within the sleeping accommodation but not the radiator where the
room thermostat is sited. This must be fitted with lock-shield valves
and left open.
• A drain cock is required at the lowest point in the system.
• An air vent is required at all the high points in the system.
4
6720643895-04.1Wo
6 720 802 047 (2013/05)