9
Depending on the water hardness and the operating
conditions, it may be necessary to descale the heating
rods at certain intervals.
The immersion heater EHE will require regular servic-
ing at a water hardness of > 1.3 mol/m
3
(7 °dH). Alter-
natively, take suitable measures to lower the lime con-
tent in the domestic water supply.
1.
Isolate the immersion heater EHE from the power
supply and safeguard against reconnection.
2.
Drain the DHW cylinder:
DHW cylinder service instructions
3.
Remove the immersion heater EHE in reverse
order to installation, see page 4.
4.
Descale the heating rods.
5.
Reinstall the immersion heater EHE, see page 4.
6.
Fill the DHW cylinder.
DHW cylinder service instructions
7.
Check the function of the safety valve.
DHW cylinder service instructions and safety
valve instructions
8.
Reconnect the power supply to the immersion
heater EHE.
Maintenance
Maintenance and service
5686 109 GB
Maintenance