33 221564F
14.11 Gas Valve
Remove the injector pipe as described in section 12.3.
Remove the gas injector as described in section 14.10.
Remove the electrical connections from the gas valve, see
diagram 11.2.
Undo the gas pipe nut from beneath the base panel.
Undo and remove the two securing screws from beneath the
base panel.
Remove the gas valve.
After replacing the gas valve the combustion CO
2
will need to
be checked and adjusted if necessary, see section 12.6.
14.12 Fan
Remove fan as described in section 12.3.
14.13 Burner
Remove fan and burner as described in section 12.3.
14.14 Pump
Refer to section 12.9 and drain the boiler heating circuit.
Undo the pump union nuts.
Unscrew the electrical cover from the pump and remove wiring.
Fit the new pump and refill, vent and pressurise the boiler.
Check for leaks.
14.15 Pressure Relief Valve
Refer to section 12.9 and drain the boiler heating circuit.
Undo the pressure relief valve unions and remove from the
pipework.
Fit new pressure relief valve.
Refill, vent and pressurise the boiler.
Check for leaks.
DOMESTIC HOT
WATER
THERMISTOR
6546
THREE WAY
VALVE HEAD
Diagram 14.1
6530
LOCATION
BUTTON
Diagram 14.3
6568
Diagram 14.2
HEATING FLOW
THERMISTOR
THERMISTOR
RETAINING CLIP
IMPORTANT NOTE:- The thermistor will
fall out of the pocket if the restraining clip
is not fitted as shown.
POCKET
ELECTRICAL
CONNECTION
(2 OFF)
SCREW
SECURING
BRACKET
14 Replacement of Parts