Heatrae Sadia Multipoint 30, Инструкция по установке и эксплуатации, Страница: 14 / 20

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6.0 MAINTENANCE
Warning: disconnect from all electrical supplies before beginning any work
on the unit. Water contained in the heater may be very hot.
To ensure the continued safe and efficient operation of the unit, it should be
regularly maintained.
Maintenance should be carried out by a competent person and any
replacement parts used should be authorised Heatrae Sadia spare parts.
Little maintenance is required, however in hard water areas the unit will
require periodic descaling to ensure efficient operation. To descale the unit:
6.1 Switch off and disconnect the electrical supply. Turn off the water
supply to the unit.
6.2 Open a hot tap to relieve any system pressure. Empty unit by
opening the drain cock in the inlet pipework.
6.3 Remove the terminal cover by using a large flat bladed screwdriver
to depress the 4 snap lugs located in the 4 rectangular depressions
on the bottom cover.
6.4 Disconnect the electrical terminations to the element. Disconnect
earth links to the earthing stud. Withdraw the thermostat and thermal
cut-out capillary tubes from the pocket on the element plate.
6.5 Remove the element plate assembly by unscrewing the five securing
screws, tapped jacking holes are provided (NOTE: a quantity of
water may still be present in the container, it is recommended that a
container be placed under the unit to collect any spillage). 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.
6.6 Re-assemble the element plate assembly fitting a new sealing
gasket. Rewire the unit with reference to the Wiring Diagrams.
6.7 Re-commission the unit following the INSTALLATION and
COMMISSIONING instructions.