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INSTALLATION
Troubleshooting
22
| DHC-E Trend & DHC-E Plus
www.stiebel-eltron-usa.com
16. 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 an error
Yellow
Lights up in heating mode/flashes when output limit
reached
Green
Flashing: Water heater connected to power supply
Diagnostic lights
Problem
Cause
Solution
No LED is lit
The water heater does not
heat up
There is no power
Check to ensure the connected circuit breaker in the main
breaker panel hasn’t tripped. Reset if necessary
The PCB is faulty
Replace the PCB
Green flashing, yellow
off, red off
No DHW
The shower head/aerator is scaled up
Descale or replace the shower head/aerators if necessary
The filter screen in the cold water inlet is dirty
Clean the filter screen
The flow sensor is not plugged in
Connect the cable to the PCB
The flow sensor is faulty
Replace the flow sensor
The PCB is faulty
Replace the PCB
Green flashing, yellow
on, red off
The display on the program-
ming unit is off
There is a loose cable between the PCB and the pro-
gramming unit
Check the cable and plug the cable into the programming
unit and/or PCB
The cable of the programming unit is faulty
Check the cable and replace if necessary
The programming unit PCB is faulty
Replace the programming unit, only available with a new
heater cover
The PCB is faulty
Replace the PCB
Green flashing, yellow
on, red off
The outlet temperature does
not match the set value
The programming unit was not plugged in before
power was switched on
Perform a reset by switching off the power to the water
heater
The outlet sensor is faulty
Replace the outlet sensor
The tap is faulty
Replace the tap
The heating system is faulty
Replace the heating system
The PCB is faulty
Replace the PCB
Plus models only:
Green flashing, yellow
The outlet temperature does
not match the set value
Motorized valve limit reached
Reduce the set temperature
flashing, red off
Motorized valve is faulty
Replace the motorized valve
Green flashing, yellow
off, red on
No DHW
Air detected
Continue draw-off for >1 minute
Diagnostic lights
Display readout
Problem
Cause
Solution
Green flashing, yellow
off, red on
Wrench flashes (displays
E1 and wrench in menu
“Fault code display”)
No DHW
AE3 safety switch not activated during
commissioning
Activate AE3 safety switch by pressing the reset button
firmly. See section 12.3.1, “Initial AE3 safety switch acti-
vation,” pg. 19
AE3 safety switch triggered by
self-resetting high limit safety cut-out
Klixon
Check high limit safety cut-out Klixon (plug-in connection,
connecting cable); activate AE3 safety switch
AE3 safety switch responds again after
high limit safety cut-out Klixon has been
checked; high limit safety cut-out faulty
Replace high limit safety cut-out, Klixon; activate AE3
safety switch and draw off water at the maximum set
value for >1 min
Safety switch responds again; PCB faulty
Replace the PCB
Wrench flashes (displays
E2 and wrench in menu
“Fault code display”)
No DHW
PCB faulty (lead break or short circuit in
inlet sensor)
Replace the PCB
Wrench flashes (displays
E3 and wrench in menu
“Fault code display”)
No DHW
Short circuit in outlet sensor
Check the outlet sensor, replace if necessary