By The Contractor - AEG DDLE LCD 18 Gebrauchs- Und Montageanweisung

7. Troubleshooting
Display options LED diagnostic "traffic lights"
Fault / Diagnostic "traffic light"
display*
Flow rate too low
Set temperature is not achieved
Heater does not switch on / no hot
water
No hot water
No "traffic light" display
No hot water; flow rate > 3 l/min
Traffic light display:
green flashing or constantly ON
No hot water; flow rate > 3 l/min
Traffic light display:
constant yellow illumination
green flashing
No hot water
Traffic light display:
constant red illumination
green flashing
Inaccurate temperature control
No "traffic light" display
No hot water
Traffic light display:
constant red illumination
Table 6

by the contractor

Red illuminates in case of faults
Yellow illuminates when the equipment is heating water
Green flashing: the device is supplied with power
Cause
Shower head/perlators scaled up
Contamination
One phase down
The air sensor detects the presence of air
in water and briefly switches the heater
off.
Fuse/MCB blown/tripped
Safety pressure limiter AP 3 has tripped
Faulty electronics
Faulty electronics
Flow sensor DFE not plugged in
Flow sensor DFE faulty
Safety pressure limiter AP 3 triggered or
cable break
Heating system faulty
Faulty electronics
Cold water inlet temperature > 35 °C
Cold water sensor faulty
Outlet temperature sensor pulled or lead
broken
Outlet sensor faulty (short circuit)
For contractors
Remedy
Descale and replace, if required.
Clean sieve ( H 28).
Check fuse/MCB (fuse box).
Device starts again after one minute.
Check fuse/MCB (fuse box).
Remove cause of fault (e.g. faulty pressure
washer).
Open downstream tap for 1 minute.
This depressurises and cools down the
heating system, protecting it against
overheating.
Press the pushbutton on the safety
pressure limiter (push A 11).
Test the electronics PCB ( A 7) and
replace, if required.
Test the electronics PCB ( A 7) and
replace, if required.
Refit the plug of the electronics PCB.
Check and replace the flow switch,
if required.
Check safety pressure limiter and replace,
if required ( A 11).
Test the heating system resistor ( A 15)
and replace, if required
Test the electronics PCB ( A 7) and
replace, if required.
Reduce the temperature of the cold water
supply to the device.
Test the electronics PCB ( A 7) and
replace, if required.
Push on outlet temperature sencor lead,
check and replace sensor/lead, if required.
Test outlet sensor and replace, if required.
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