11
6.0 MAINTENANCE
Warning: disconnect from all electrical supplies before beginning any work on
the unit. Water contained within the unit may be very hot!
Maintenance should be carried out by a competent person and any replacement
parts should be authorised Supplier spare parts.
It is recommended that maintenance is carried out regularly and should include
the checks detailed in the sections below.
6.1 Little maintenance is required, however in hard water areas the unit
will require descaling approximately every two years to ensure efficient
operation. The magnesium anode should be replaced every two
years.
To carry out this operation:
6.1.1 Switch off and disconnect the electrical supply. Turn off the water
supply to the unit.
6.1.2 Open a hot tap to relieve any system pressure. Disconnect the
plumbing connections to the unit and remove from the wall (note full
weights of units in Section 2). Empty unit by tipping through 90° over
a sink.
6.1.3 Remove the top cover by removing the two recessed self-tapping
screws on the top of the unit.
6.1.4 Prise off the front temperature control knob which is attached to the
thermostat spindle.
6.1.5 The top cover can now be removed by lifting vertically.
6.1.6 Carefully remove retaining plug and both capillary sensors from the hole
in the circular element plate but avoid kinking or straining the capillary
tubes.
6.1.7 Remove the earth wire from the element plate.
6.1.8 Remove the element plate assembly by removing the four securing
nuts. Remove any loose scale from the container. Carefully clean off
any scale from the element and thermostat pocket. DO NOT clean
scale from interior container walls
.
6.1.9 To replace the magnesium anode, unscrew from the element assembly.
Fit the new anode as a reversal of this procedure.
6.1.10 Refit the element plate assembly, fitting a new sealing gasket if required.
Note the correct orientation of the element plate by reference to Figure
06, page 12. Refit the capillary sensors, retaining plug and earth wire.
Refit the cover, insert the two self-tapping screws to secure and refit
the temperature control knob.
