Worcester GREENSTAR 12i Instruction Manual page 51

23.1
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR 12i/24i System
8 716 115 167b (03/2009)
22.1
22.2
23.2
A
REPLACEMENT OF PARTS
22. Hydraulic Block
Ensure the appliance has been fully drained.
Disconnect the electrical connections at the
pump.
Remove the syphon assembly (see page 49).
Undo the nuts securing the copper water
pipes to the manifold (there is no need to
remove the gas pipe).
Release the spring clips securing these
water pipes to the plastic housing and
remove the pipes.
Release the spring clip securing the
expansion vessel pipe to the plastic housing
and remove the pipe.
Push up on the pressure gauge bracket to
release the bracket and gauge from the
frame.
Release the locking devices that secure the
two copper water pipes leading to the
combustion chamber by squeezing the two
tabs together and rotating anticlockwise
(viewed from above).
22.1 Undo the two screws securing the hydraulic
block to the chassis (located top left / top
right of the housing)
22.2 Lift the left hand side of the block slightly,
then manoeuvre the block out, starting with
the right hand side.
Take care not to snag the harness or
pressure gauge bracket.
NOTE: the block will still contain a small amount
of water, which will spill if the block is tilted.
To refit, follow the above in reverse. Ensure
any seals that have been disturbed are
renewed.
23. CH pressure relief valve
Remove the hydraulic block from the boiler
(See Removing the Hydraulic Block).
23.1 Release the captive spring clip from the
pressure relief valve housing.
23.2 Withdraw the pressure release valve (A) from
its housing.
To refit, follow the above in reverse. Ensure
any seals that have been disturbed are
renewed.
REPLACEMENT OF PARTS
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