Glow-worm Ultrapower sxi Series Installation And Servicing page 62

15 Replacement of Parts
15.18 Safety Discharge Valve
For access, refer to section 15.1.
LOW WATER
Refer to section 15.1 and drain the boiler heating circuit.
PRESSURE
The safety discharge valve is situated towards the RH side of
SENSOR
the boiler module, refer to diagram 15.14.
Unscrew the pipework union nut from the safety discharge
valve.
Remove the securing clip and withdraw the safety discharge
valve.
Fit new 'O' ring.
15.19 Domestic Water Thermistor
For access, refer to section 15.1.
The domestic hot water thermistor is situated centrally in the
boiler module on the DHW inlet pipe, refer to diagram 15.15.
DOMESTIC
Disconnect the domestic hot water thermistor electrical
WATER
connections
THERMISTOR
Remove hot water thermistor.
Diagram 15.15
NOTE: When reconnecting electrical connections, polarity is
not important.
Carry out a functional test of the controls.
HEAT EXCHANGER
15.20 Heating Flow Thermistor
For access, refer to section 15.1.
The primary flow thermistor is situated underneath the heat
exchanger, refer to diagram 15.16.
Remove the electrical connections from the thermistor.
Remove the thermistor noting its position on the flow pipe.
NOTE: When reconnecting, the polarity of the wiring to
thermistors is not important.
HEATING
FLOW
THERMISTOR
SECURING
CLIP
UNION
Diagram 15.16
NUT
SAFETY
DISCHARGE
VALVE
Diagram 15.14
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