10 Maintenance
70
Combi 2
Fig.84
Remove hall effect sensor
Fig.85
Remove safety pressure relief valve
1.
Ease the sensor upwards off the hydraulic inlet manifold assembly.
2.
Disconnect the electrical plug from the sensor.
3.
Connect the plug to the new sensor. Carefully fit the new sensor to
the hydraulic assembly, ensuring it is fully down.
10.4.8
Replacing the s
afety pressure relief valve
1.
Disconnect the power supply to the boiler;
2.
Close the gas cock;
3.
Cut off the gas supply to the boiler.
4.
Close the heating system return and flow cocks.
5.
Drain the system, if possible, only the boiler, using the specific
drain cock.
6.
Empty the water from the domestic water circuit by opening a user
cock.
7.
Disconnect the discharge pipe from the valve and remove the seal-
ing grommet.
8.
Using a suitable hexagon key, undo the grub screw sufficiently
to re-lease the valve.
9.
Note the orientation of the valve, rotate it and withdraw it from the
manifold.
10.
Fit the new valve and ‘O’ ring seal and set to the previously noted
orientation. Tighten the grub screw.
11.
Reconnect the discharge pipe ensuring the sealing grommet is in
place to maintain the integrity of the case seal.
Fig.86
Remove diverter valve
10.4.9
Replacing the d
iverter valve motor
1.
Disconnect the multi-pin plug from the diverter valve motor.
2.
Hold the motor in place against the spring pressure of the valve
assembly, remove the securing clip (1).
3.
Remove the motor (2).
4.
When fitting the new motor, it will be necessary to hold the unit
firmly while depressing the valve assembly spring to refit the
securing clip.
5.
Reconnect the multi-pin plug.
10.4.
7
Replacing the hall effect sensor
