Moving Controls To Service Position; Gas Valve; Air/Gas Manifold And Fan Assembly - Worcester Greenstar i Series Installation, Commissioning And Servicing Instructions

SERVICE AND SPARES
1.
Fig. 91 Remove thermostat
To replace, push the thermostat and grommet gently back into the
opening until contact with the locating ridge is felt.

6.8.5 MOVING CONTROLS TO SERVICE POSITION

To remove the following components require the control
box must be moved in to the service position:

▶ Gas valve

▶ Syphon
▶ PCB
▶ Fuse
NOTICE: REPLACEMENT OF THE GAS VALVE MUST
NOT BE CARRIED OUT IF A CO/CO
AVAILABLE.
1. Remove the screw securing control panel.
2. Gently pull the panel forward.
1.
2.
Fig. 92 Control panel to service position
6.8.6 GAS VALVE
▶ Isolate gas supply at boiler gas cock.
1. Refer to figure 93 and remove wire clip from the gas valve outlet.
2. Pull the gas pipe free from the gas valve.
If the pipe will not pull out, unscrew the nut to aid removal.
40
Fig. 93 Gas valve upper connection
1. Refer to figure 94 and undo bottom gas connection to gas valve.
2. Undo two securing screws on the underside of casing.
▶ Disconnect electrical connections.
▶ Pull valve up and forward out of boiler.
▶ Replace valve with new seals and check for gas tightness.
ANALYSER IS NOT
2
Fig. 94 Gas valve lower connection

6.8.7 AIR/GAS MANIFOLD AND FAN ASSEMBLY

▶ Remove electrical connector and earth wire the from fan.
▶ Remove wire clip from gas valve outlet then pull gas pipe free from the
2.
2.
NOTICE: The valve will require setting; follow
procedure "Setting the air/gas ratio".
The following components require the
air/gas manifold and fan assembly to be removed:
▶ Fan electrode assembly
▶ Burner
▶ Heat exchanger
NOTICE:
▶ If the joint between the Air/Gas manifold and heat
exchanger is disturbed sealing gasket must be
replaced.
▶ After re-assembly the combustion must be checked
using the procedure in the section "Setting the Air/
Gas ratio". Measurement and setting (if necessary) of
the gas ratio must not be attempted unless the person
is equipped with a combustion analyser conforming to
BS 7927 and is competent in its use.
gas valve (see figure 93).
1.
6720643895-72.1Wo
1.
6 720 804 532 (2012/09)