WATER TREATMENT
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR HEATSLAVE EXTERNAL 12/18-18/25-25/32
8 716 113 389b (09/07)
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WATER TREATMENT
IMPORTANT: 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.
FLUSHING (Central Heating):
1
Switch off the boiler.
Open vented systems only: turn off the
water to the system header tank.
Open all radiator valves/drain cocks (C) and
drain the system while the appliance is hot.
Close drain cocks (C).
2
Add a suitable flushing agent (F) and refill
the system at the correct strength for the
system condition in accordance with the
manufacturer's instructions.
Vent the boiler (there are two vent points
(A) at the top of the secondary heat
exchanger. Only one may be in use, the
other may be obscured by side fluing.
Always vent (A) and the vent screw (B) on
the pump and all radiators.
Run the boiler/system at normal operating
temperature for the time stated by the
flushing agent manufacturer.
3
Drain and thoroughly flush the system and
boiler to remove the flushing agent and
debris (C).
INHIBITOR (Central Heating):
4
Check drain cocks (C) and manual air vents
are closed and all radiator valves are open.
5
Add a suitable inhibitor (I), (or combined
inhibitor/anti-freeze if the system is exposed
to freezing conditions) to the heating system
in accordance with the manufacturers
instructions.
The inhibitor or combined inhibitor/anti-freeze
must not cause damage to the materials within
the boiler (mild steel, stainless steel, copper
and brass) and any other materials/components
within the system.
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 2 bar via a WRAS approved
filling loop. Check the system pressure
during venting and repressurise if
necessary.
6
Vent the boiler (there are two vent points
(A) at the top of the secondary heat
exchanger. Only one may be in use, the
other maybe obscured by side fluing.
Always vent (A) and the vent screw (B) on
the pump and all radiators; retighten vents
when complete.
7
Record the date when the inhibitor was
added to the system on the guarantee card.
NOTE: The concentration level of inhibitor
in the system should be checked every 12
months or sooner if system content is lost.
The addition of sealing agents to the system
water is not advised as this can cause
problems with deposits left in the heat
exchanger and invalidate the appliance and
heat exchanger warranty .
2
1
3
4
5
6
1 - 2 bar
A
A
B
B
C
C
C
C
C
