Diverter Valve; Diverter Valve Motor; Sensors - Worcester benchmark ZWB 7-25 R 25 HE Design, Installation And Servicing Instructions

Maintenance
8.3.4

Diverter valve

B Switch off the appliance.
B Disconnect appliance from the power supply.
B Turn off service cocks.
B Unplug connector from 3-way valve motor. Refer to
fig. 63.
B Pull out retaining clip.
B Remove motor.
B Disconnect the relief valve drain.
B Disconnect the pressure gauge by withdrawing the
clip and pulling out the capillary head.
B Undo pipe unions by withdrawing the clips.
B Remove 3-way valve.
Fig. 63
After refitting:
B Fill system, bleed and re-pressurise
(see Installation Instructions).
8.3.5

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. 63.
B Pull out retaining clip.
B Remove motor.
40
8.3.6

Sensors

B Check that the appliance is electrically isolated.
Central Heating Flow Temperature Sensor –
Item 36, fig. 2, 59
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, 59
B Pull-off the connectors.
B Unscrew the sensor.
Flue Temperature Limiter – Item 9, fig. 2, 59
B Pull-off the connectors.
B Unscrew the sensor.
Domestic Hot Water Temperature Sensor –
Item 6.1, fig. 2
B Check that the inlet water valve is closed and the
domestic hot water circuit is drained.
B Release and pull-off the connector.
B Unscrew the sensor.
7 181 465 330-12.1R
6 720 611 441 GB (03.11)