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INSTALLATION
Troubleshooting
14. Troubleshooting
Note
The high limit safety cut-out can respond at temperatures
below –15 °C. The appliance may be subjected to these
temperatures during storage or transport.
Fault
Cause
Remedy
The water does not
heat up.
The high limit safety
cut-out has responded
because the controller is
faulty.
Replace the thermostat
and press the high limit
safety cut-out reset but-
ton.
The high limit safety cut-
out has responded be-
cause the temperature has
dropped below -15 °C.
Press the reset button.
A heating element is
faulty.
Replace the flanged im-
mersion heater.
Rapid heating does not
switch on.
Check the contactor and
replace if required.
The safety valve drips
when the heating is
switched off.
The valve seat is contam-
inated.
Clean the valve seat.
26
�0
2�
09
�0
07
0�
1
1 High limit safety cut-out reset button
15. Maintenance
WARNING Electrocution
Carry out all electrical connection and installation work
in accordance with relevant regulations.
WARNING Electrocution
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".
15.1 Checking the safety valve
f
f
Regularly vent the safety valve on the safety assembly until a
full water jet is discharged.
15.2 Draining the appliance
WARNING Burns
Hot water may escape during the draining process.
If the cylinder needs to be drained for maintenance or to protect
the whole installation when there is a risk of frost, proceed as
follows:
f
f
Close the shut-off valve in the cold water line.
f
f
Open the hot water taps on all draw-off points.
f
f
Drain the appliance via the safety assembly.
15.3 Replacing the signal anode
f
f
Replace the signal anode if it becomes depleted.
15.4 Cleaning and descaling the appliance
f
f
Never use descaling pumps.
f
f
Only descale the flanged immersion heater after dismantling
and never treat the cylinder surface or protective anode with
descaling agents.
Torque of the flange screws: see chapter "Specification / Dimen-
sions and connections"
15.5 Replacing flanged immersion heater
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�0
2�
09
�0
06
9�
5
6
4
2
3
1
1 Insulation plate
2 Flange plate
3 Soldered flange
4 Insulating plate
5 Corrosion resistor 390 Ω
6 Gasket
The corrosion resistor acts to balance the potential and prevents
power leakage corrosion on the heating elements.
f
f
Never damage or remove the corrosion resistor during
maintenance.
f
f
After replacing the corrosion resistor, reassemble the flanged
immersion heater correctly.