Troubleshooting - Stiebel Eltron DHC 3/3.5-1 Trend Utilisation Et Installation

INSTALLATION

Troubleshooting

15. Troubleshooting
WARNING Electrocution
Never remove or reinstall the water heater's cover unless
the electricity servicing the unit is turned off. Failure to
do so could result in personal injury or death.
WARNING Electrocution
To test the water heater using the internal diagnostic
lights, it must be connected to the power supply.
When testing with the cover off, never touch any part of
the water heater. Doing so could result in serious per-
sonal injury or death.
Note
When testing the water heater using the diagnostic lights,
water must be flowing through the unit.
Diagnostic lights
Red Lights up in the event of a fault
Yellow Lights up in heating mode/flashes when output limit
reached
Green Flashing: Water heater connected to power supply
Diagnostic lights Problem
No LED is lit The water heater does not
heat up
Green flashing, yellow No DHW
off, red off
Green flashing, yellow The outlet temperature does
on, red off not match the set value
Green flashing, yellow No DHW
off, red on
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Cause
There is no power
The PCB is faulty
The shower head/aerator is scaled up
The filter screen in the cold water inlet is dirty
The flow sensor is not plugged in
The flow sensor is faulty
The PCB is faulty
The device is connected to a power supply <240 V
The tap is faulty
The heating system is faulty
The PCB is faulty
Air detected
AE3 safety switch not activated during commission-
ing
AE3 safety switch triggered by self-resetting high
limit safety cut-out
AE3 safety switch responds again after high limit
safety cut-out Klixon has been checked; high limit
safety cut-out faulty
Safety switch responds again; PCB faulty
PCB faulty (lead break or short circuit in inlet sen-
sor)
Solution
Check to ensure the connected circuit breaker in the main
breaker panel hasn't tripped. Reset if necessary
Replace the function module
Descale or replace the shower head/aerator if necessary
Clean the filter screen. See section 14.2, "Cleaning the
filter screen," pg. 14
Connect the cable to the PCB
Replace the function module
Replace the function module
Please observe the information in section 11.1, "Tem-
perature setting via jumper slot", pg. 12
Replace the tap
Replace the function module
Replace the function module
Continue draw-off for >1 minute
Activate AE3 safety switch by pressing the reset button
firmly. See section 11.3.1, "Initial AE3 safety switch acti-
vation," pg. 13
Check high limit safety cut-out Klixon (plug-in connec-
tion, connecting cable); activate AE3 safety switch
Replace high limit safety cut-out Klixon activate AE3
safety switch and draw off water at the maximum set
value for >1 min
Replace the function module
Replace the function module
DHC Trend | 15