Worcester GREENSTAR 12i Instruction Manual page 44

A
44
REPLACEMENT OF PARTS
5.1
INSTALLATION & SERVICING INSTRUCTIONS FOR WORCESTER GREENSTAR 12i/24i System
REPLACEMENT OF PARTS
5.2
SIT AND DUNGS VALVES
The following components require
the control to be moved in to the
service position:
Gas valve
Siphon
PCB fuse
Transformer
REMOVAL OF THE VALVE IS THE SAME
FOR BOTH SIT AND DUNGS VALVES. THE
SIT VALVE IS SHOWN IN THE DIAGRAM.
R E P LAC E M E NT OF TH E GAS VALVE
M U ST NOT B E C AR R I E D OUT I F A
6.1
CO/CO2 ANALYSER IS NOT AVAILABLE.
5. Moving boiler control to service
position
5.1 Remove screw (A) securing control.
5.2 Gently pull forward.
6. Gas valve*
Isolate gas supply at boiler gas cock.
6.1 Remove wire clip from gas valve outlet then
pull gas adjustment assembly free from
plastic connector and pull forward clear of
case.
6.2 Undo bottom gas connection to gas valve.
6.3 Undo two securing screws (C) on the
6.2
underside of casing.
Pull valve up and forward out of boiler.
Disconnect electrical connections.
Replace valve with new seals and check for
gas soundness.
NOTE: The valve will require setting; follow
6.3
C
8 716 115 167b (03/2009)
procedure "Setting the air/gas ratio".