Operating Instructions and Installation Instructions

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INSTALLATION
Troubleshooting
13. Troubleshooting
WARNING Electrocution
In order to check the appliance it must be connected to
the power supply.
13.1 Indicator options for LED diagnostic traffic light
Indicator options
Red Illuminates in the event of a fault
Yellow Illuminates during heating mode
Green Flashing: Appliance is supplied with mains power
13.2 Fault table
Fault / diagnostic traffic light LED
display
Cause Remedy
The appliance does not start. The shower head / aerators are scaled up. Descale or if necessary replace the shower head / aera-
tors.
Inadequate flow rate. The strainer in the appliance is dirty. Clean the strainer.
The set temperature is not achieved. One phase down. Check the fuses/MCBs in your fuse box/distribution panel.
The heater switches off. The air sensor detects the presence of air in the water
and briefly interrupts the heating output.
The appliance restarts after one minute.
No hot water and no traffic light display.
The MCB/fuse has responded/blown. Check the fuses/MCBs in your fuse box/distribution panel.
Safety pressure limiter AP 3 has tripped.
Remove the cause of the fault (e.g. faulty pressure wash-
er).
Protect the heating system against overheating by open-
ing a draw-off valve downstream from the appliance for
one minute. This depressurises and cools down the heat-
ing system.
Activate the safety pressure limiter at flow pressure by
pressing the reset button; see also chapter "Commission-
ing/ Initial start-up".
The PCB is faulty. Check the PCB and replace if necessary.
Traffic light display: Green flashing
No hot water at flow rate >3l/min.
Flow sensor DFE is not plugged in. Plug the flow sensor plug back in.
Flow sensor DFE is faulty. Check the flow sensor and replace if necessary.
The set temperature is not achieved.
The set value transducer or connecting cable is faulty, or
the connecting cable is not attached.
Attach the connecting cable; replace the set value trans-
ducer if required.
Temperature limiting is activated. Disable temperature limiting.
Traffic light display: Yellow constantly on;
green flashing
No hot water at flow rate >3l/min.
The high limit safety cut-out has responded or its lead
is broken.
Check the high limit safety cut-out and replace if neces-
sary.
The heating system is faulty. Measure the resistance of the heater and replace if nec-
essary.
The PCB is faulty. Check the PCB and replace if necessary.
Traffic light display: yellow constantly on;
green flashing
The outlet sensor is faulty. Check the connection and replace the outlet sensor if
necessary.
Set temperature is not achieved. Appliance is operating at its output limit. Reduce the flow rate or install the flow limiter.
Traffic light display: red constantly on; green
flashing
The outlet sensor is faulty. Check the connection and replace the outlet sensor if
necessary.
No hot water
The cold water sensor is faulty. Check the PCB and replace if necessary.
Required temperature >45°C not achieved The cold water inlet temperature exceeds 45°C. Reduce the cold water inlet temperature to the appliance.