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8
MAINTENANCE
Isolate all electrical supplies before removing any components for inspection or repair, or
before draining the cylinder or heat source circuits.
The pressure relief valves must be operated regularly to remove lime deposits and to verify
they are not blocked.
8.1
Regular Maintenance
This appliance must be serviced annually to ensure continued safe operation and to maintain the
guarantee. Servicing must be undertaken by a competent person i.e. qualified professional.
1
Isolate the mains water supply and open a hot tap. Check the expansion vessel bladder
pre-charge
– it should be 3.0 bar.
2
Check the strainer on the inlet group. Clean the strainer if necessary by unscrewing
the pressure reducing valve and withdrawing the strainer.
3
Check and service all hard water treatment devices (if fitted) in accordance with each
device manufacturer’s instructions.
4
Check that all connections are tight and correctly configured.
5
Manually operate (by rotating the knob) both the expansion relief and the temperature
and pressure relief valves to prove the correct function of the discharge arrangement.
6
Check all joints for leaks and rectify as necessary.
7
Check that all immersion and control thermostats are appropriately set.
8
Activate each heat source to confirm that the system controls function correctly.
9
Check that, while the cylinder is heating up, no water exits from either the expansion
relief or the temperature and pressure relief valves, and that the system controls
deactivate all heat sources when the cylinder is up to temperature.
8.2
Inspection Access
Where necessary, the internal components of the cylinder can be inspected by means of the
immersion heater boss (1¾”) using an appropriate inspection tool e.g. borescope.
8.3
Replacement Parts
Part description
Code
Cylinder thermostat
WDS7
Immersion heater c/w stat (1¾”)
3602
Motorised valve (22mm)
3603
T&P valve
(½” x 15mm)
3654
Inlet group (22mm)
3890
Expansion vessel (12 litres)
3891
Expansion vessel (19 litres)
3892
Expansion vessel (24 litres)
3893
Tundish (15mm x 22mm)
3670
Cylinder Plate Heat Exchanger 4384
Potable Water Circulating Pump 4383
