30
Display options LED diagnostic “traffic lights”
red
illuminates in case of faults
yellow
illuminates when the equipment is heating water
green
flashing: the device is supplied with power
Fault / Diagnostic
“traffic light” display*
Cause
Remedy
Flow rate too low
Shower head/perlators scaled up
Contamination
Descale and replace, if required.
Clean sieve (
H
28)
Set temperature is not achieved
One phase down
Check fuse/MCB (fuse box).
Heater does not switch on / no hot
water
The air sensor detects the presence of air
in water and briefly switches the heater
off.
Device starts again after one minute.
No hot water
Fuse/MCB blown/tripped
Check fuse/MCB (fuse box).
No “traffic light” display
Safety pressure limiter AP 3 has tripped
Faulty electronics
Remove the cause for the 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.
No hot water; throughput> 3 l/min
Traffic light display:
green flashing or constantly ON
Faulty electronics
Flow sensor DFE not plugged int
Flow sensor DFE faulty
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.
6. Troubleshooting
by the user
For users and contractors
7. Troubleshooting
by the contractor
Fault
Cause
Remedy
The heating system inside the
instantaneous water heater will not
start in spite of the tap being fully open.
No voltage.
User / Contractor:
Check the fuses in your fuse board.
The start-up volume required to start the
heater has not been reached.
Contamination or scaling of perlators in
water taps or shower heads.
User / Contractor:
Clean and / or descale.
Heating system faulty.
Call service / contractor:
Test heater and replace, if required.
Intermittent cold water
The air sensor detects the presence of air
in water and briefly switches the heater
off.
Device starts again after one minute.
Table 5
