Maintenance
a) For the user
In order to obtain the best performance from the heater, the sacrificial anode must
be checked every year and replaced as necessary. If the heating element is heavily
coated with scale we recommend descaling and removing any lime deposit from the
heater at the time of this inspection. Where the additional cold water controls are
fitted, the expansion vessel will need to be recharged by the installer.
Important note: The heater must be serviced annually. Failure to service which
includes inspection and replacement of the sacrificial anode will invalidate
warranty.
b) For the installer
WARNING: Switch off the power first
Access to the electrical components, the magnesium anode and water container is
gained by unscrewing the 2 screws on the front cover.
If the thermal cut-out has operated the cause must be found before resetting.
To drain the heater close the service valve and:
i) for under-sink models disconnect pipes and removed the heater from the wall.
ii) for over-sink models undo the cold water supply pipe and open a hot water tap.
The heating element may be removed (after taking out the thermostat phials on
model 30 L) by undoing the M6 nut.
The assembly should then be turned through 90° anti-clockwise to ease removal
from the water container.
Once the element is free from the water container the anode may then be
inspected and removed if necessary.
When reassembling the cover make sure that the regulation knob is coupled with
the thermostat.
Check controls (where fitted) as per the following:
- Line strainer - with the water supply turned off remove screen from strainer and
clean of any detritus;
- Expansion vessel - with the water supply turned off and taps open, check expansion
vessel pressure and top up as necessary;
- Temperature & pressure relief valve - with the water supply turned on, check
manually by lifting the test lever/turning the test knob (ensure valve closes after
testing);
- Expansion relief valve - check manually by turning the test knob (ensure valve
closes after testing);
- Discharge pipes (D1) - from both temperature & pressure relief and expansion relief
valve for obstructions;
- Tundish & discharge pipe (D2)- open either valve gradually to produce a full bore
discharge into tundish and D2 without any back pressure;
- Pressure reducing valve - check that the correct outlet pressure is being maintained
by recording the pressure at an in-line terminal fitting i.e. tap.
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