Bosch Worcester GREENSTAR 12Ri ErP +, Installation And Maintenance Instructions Manual, Page: 30 / 68

PRE-INSTALLATION
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4.9 CLEANING PRIMARY SYSTEMS
Before cleaning the system:
▶ Ensure that the system and pipe work is in good working order.
▶ Where possible keep the existing appliance/circulating pump in
place when flushing the system before installing the new
appliance. Alternatively use an after market power flushing
system or similar to remove magnetite and other debris from the
central heating system.
– Even new central heating systems contain contaminants that
need to be removed before treating the system with inhibitor/
antifreeze.
– When an appliance is installed onto a new system then it is
possible to use the appliance whilst cleaning the system. There is
a risk that debris could damage the appliance and reduce
efficiency. A system filter must be fitted to the return to reduce
the risk of contaminants entering the appliance.
▶ Follow the guidance of BS7593.
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.
Products approved to the BuildCert standard are deemed as compatible
with the components and equipment within the appliance and system.
Water treatment products
Suitable water treatment products can be obtain from the following
manufacturers:
4.9.1 Flushing the system
▶ Fill the system with cold water and check for leaks.
▶ Open vented systems only:
– Turn off the water to the system header tank.
▶ 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 between 6.5 and 8 or
the appliance guarantee will be invalidated.
▶ Mark the position of the lockshield valves and open them fully.
▶ Fully open all TRVs.
▶ Circulate the flushing agent before the appliance is fired up.
▶ Run the appliance/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. Do not drain the system through the PRV of new
appliances.
▶ It may be necessary to use a power flushing machine to aid the
cleansing procedure in some circumstances.
▶ Close the drain cocks and manual air vents.
▶
Existing appliance/circulating pump if continuing to use before
new appliance is installed.
– Add a suitable inhibitor to the system in accordance with the
manufacturers instructions.
– Open vented systems only:
Turn on the water to the system header tank and allow the system
to fill.
– Sealed systems only:
Fill the system to between 1 and 1.5 bar via a WRAS approved
filling loop.
– Vent any air from the appliance and system.
▶ New appliance.
– Once the new appliance has been installed follow the guidance in
Filling the appliance and adding inhibitor section.
NOTICE: Debris from the system can damage the
appliance and reduce efficiency.
Failure to comply with the guidelines for the use of water
treatment with the appliance will invalidate the
appliance guarantee and contravene the Building
Regulations.
▶ It is a requirement of the Building Services
Compliance Guide which is a second tier document
to the Building Regulations to flush and inhibit the
primary water system in accordance with BS 7593.
▶ The Building Services Compliance Guide
recommends that a primary water cleanser is fitted to
the system.
▶ Worcester Bosch recommend fitting a filter that will
help remove both magnetite and non-magnetic
debris.
▶ Worcester offers two filters that helps remove both
magnetite and non-magnetic debris; 22mm version,
part number 7 733 600 236 and a 28mm version,
part number 7 733 600 237.
NOTICE: Risk of damage to system or appliance!
Artificially softened water must not be used to fill the
central heating system.
▶ Salt based, artificially softened water MUST NOT be
used to fill the system.
NOTICE: Sealing agents
When an appliance is installed onto a new system.
▶ In cases where all attempts to find a system micro
leak have failed, Worcester, Bosch Group supports
the use of Fernox F4 leak sealer.
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.
ADEY 01242 546717
www.adey.com
FERNOX 0870 601 5000
www.fernox.com
SENTINEL 0800 389 4670
www.sentinel-solutions.net
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