Pre-Installation; Cleaning Primary Systems; Mains Supply; Electrical Supply - Bosch Worcester 27Ri Compact ErP Installation, Commissioning And Servicing Instructions

4

PRE-INSTALLATION

4.1

Cleaning primary systems

NOTICE:
▶ All the following pre-installation sections must be
read and requirements met before starting boiler or
flue installations.
CAUTION:
▶ Isolate the mains electrical supply before starting any
work and observe all relevant safety precautions.
NOTICE:
▶ Debris from the system can damage the boiler and
reduce efficiency.
Failure to comply with the guidelines for the use of
water treatment with the appliance will invalidate the
appliance warranty and contravene the Building
Regulations.
▶ It is recommended that you fit a primary water
cleanser to the system. Worcester offers a filter that
helps remove both magnetite and non-magnetic
debris.
Part number 7 716 192 609
Before cleaning the system:
▶ Ensure that the system and pipe work is in good working order.
▶ Where possible keep the existing boiler/circulating pump in
place when flushing the system.
Follow the guidance ofBS7593:
Treatment of water in domestic hot water central heating and also the
flushing guidelines below.
Artificially softened water
NOTICE: ARTIFICALLY SOFTENED WATER MUST NOT
BE USED TO FILL THE CENTRAL HEATING SYSTEM.
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 level of the water. With these devices it may not be
necessary to provide an untreated water bypass to the primary water
filling point of the heating system.
Flushing the system
▶ Fill the system with cold water and check for leaks.
▶ Open all drain cocks and drain the system.
▶ Close drain cocks and add a suitable flushing agent compatible with
aluminium at the correct strength for the system conditions in
accordance with the manufacturer's instructions.
The pH value of the system water must be less than 8 or the
appliance guarantee will be invalidated.
▶ Circulate the flushing agent before the boiler is fired up.
▶ Run the boiler/system at normal operating temperature as directed
by the manufacturer of the flushing agent.
▶ Drain and thoroughly flush the system to remove the flushing agent
and debris.
▶ It may be necessary to use a power flushing machine to aid the
cleansing procedure in some circumstances.
▶ Close the drain cocks and refill with fresh water and a suitable
inhibitor.
▶ Vent any air from the boiler and system.
Greenstar Ri Compact ErP 6720813282 (2014/09)
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
▶ 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
Suitable water treatment products can be obtained from the following
manufacturers:
FERNOX 0870 601 5000 - www.fernox.com
SENTINEL 0800 389 4670 - www.sentinel-solutions.net
4.2

Mains supply

4.2.1

Electrical supply

• Supply: 230V - 50 Hz, 50 Watts plus pump
• Cable: PVC insulated 0.75mm
90 °C.
• External 3A fuse to BS1362.
• The appliance must be earthed.
• This appliance must NOT be connected to a three phase supply.
• IPX4D.
• Wiring must comply with the latest edition of BS 7671 (IET wiring
regulations).
4.2.2

Gas supply

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, the following applies:
• 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.
• Gas pipe sizing should be calculated to ensure no more than the
permitted mbar drop between the meter/governor to the appliance
inlet. ( Commissioning section).
• The meter or regulator and pipe work to the meter must be checked,
preferably by the gas supplier.
4.3

Water systems and pipe work

Plastic pipework:
• 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 under-floor 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) 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.
Pre-installation
2
(24 x 0.2mm) temperature rated to
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