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Installation - for contractors
14.
Maintenance
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Carry out all electrical connection and installation
work in accordance with relevant regulations.
Before any work on the appliance, disconnect all
poles of the appliance from the power supply.
If you need to drain the appliance, observe chapter
"Draining the appliance".
14.1
Checking the safety valve
» Test the safety valve regularly.
14.2
Draining the appliance
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Hot water may escape during the draining process.
If is necessary to drain the cylinder for maintenance or
to protect the whole installation from frost, proceed as
follows:
» Close the shut-off valve in the cold water feed line.
» Open the DHW valves of all draw-off points until the
appliance is fully drained.
» Drain any residual water from the safety valve.
14.3
Checking / replacing the protective
anode
»
Check the protective anode after the first year of use
and replace if necessary.
» Next, decide the time intervals at which further
checks should be carried out.
14.4
Descaling
» Remove loose scale deposits from the water heater.
» If necessary, descale the inner cylinder with com-
mercially available descaling agents.
»
Only descale the flange after disassembly and never
treat the cylinder surface and protective anode with
descaling agents.
14.5
Anti-corrosion protection
Ensure that while carrying out maintenance work the an-
ti-corrosion protection (560 Ω) is not damaged or removed.
Reinsert the anti-corrosion protection correctly after re-
placement.
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14.6
Replacing the power cable
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The power cable must only be replaced (for example
if damaged) with the original spare part by a quali
-
fied contractor authorised by the manufacturer.
14.7
Replacing the combined controller/
limiter
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1 Controller sensor
2 Limiter sensor
» Insert the controller sensor and the limiter sensor
into the sensor well as far as they will go.