6 720 611 449 GB (03.11)
Maintenance
43
B
Undo pipe unions by withdrawing the clips.
B
Remove 3-way valve.
Fig. 58
After refitting:
B
Fill system, bleed and re-pressurise
(see Installation Instructions).
9.3.5
3-way diverter valve motor
B
Switch off the appliance.
B
Turn off the service cocks.
B
Unplug connector from 3-way valve motor. Refer to
fig. 58.
B
Pull out retaining clip.
B
Remove motor.
9.3.6
Sensors
B
Check that the appliance is electrically isolated.
Central Heating Flow Temperature Sensor –
Item 36, fig. 2, 54
B
Pull-off the connector.
B
Release the sensor clip and withdraw the sensor.
B
Apply heat transfer paste to the replacement sensor.
Safety Temperature Limiter – Item 6, fig. 2, 54
B
Pull-off the connectors.
B
Unscrew the sensor.
Flue Temperature Limiter – Item 9, fig. 2, 54
B
Pull-off the connectors.
B
Unscrew the sensor.
9.3.7
Gas Valve
B
Check that the gas cock is turned off.
B
Lower the control panel. Refer to fig. 57.
B
Pull off the solenoid connections at the rear of the
valve.
B
Undo the union, within the inner casing, securing the
valve to the gas/air tube. Refer to fig. 56.
B
Remove the white plastic cap from the gas valve.
B
Release the gas inlet union at the manifold assembly.
B
Unscrew the two screws securing the gas valve
assembly bracket to the back panel and withdraw the
assembly.
B
Transfer the bracket and inlet pipe assembly to the
new gas valve.
B
Check for gas soundness when the new gas valve
has been fitted.
B
Recheck the combustion performance as described
in section 8.1.
Fig. 59
7 181 465 330-12.1R
6 720 610 602 - 04.1O
