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www.stiebel-eltron.com
LWZ 304-404 SOL |
43
INSTALLATION
Troubleshooting
No. Fault
Appliance response
Cause
Remedy
15
DHW temperature
DHW heating has developed
a fault if the set DHW temper-
ature in the cylinder has not
been reached after the defined
time (see "Maximum duration
DHW heating"). DHW heating is
blocked until 22:00 h and then
restarted. If the set DHW tem-
perature is not reached again,
DHW heating is blocked until
22:00 h the following day.
The electric emergency/booster
heater stages for DHW operation are
not enabled or are blocked by the
high limit safety cut-out. It may then
no longer be possible to reach the
required DHW temperature at DHW
temperatures above 50 °C and high
outside temperatures. This can hap-
pen even if a pasteurisation tempera-
ture above 50 °C is entered.
Check whether the high limit safety cut-out for the emergency/
booster heater stages has responded (see fault 02). Reset the
high limit safety cut-out, if necessary. If the high limit safety
cut-out had responded, the flow rate was probably too low (see
fault 03). Starting “DHW ECO” may provide a remedy.
The DHW diverter valve does not
work.
Multiple attempts by adjusting the set DHW temperature to
10 °C and 50 °C.
The maximum flow temperature for
DHW mode ("MAX FLOW TEMP DHW")
is set too low.
Notify customer support if the fault repeats.
16 EVE no output
Press the electronics reset button. If this faults occurs repeat-
edly, notify customer support.
17
Defrost time ex-
ceeded
The evaporator is not defrosted
within the defined period. The
compressor will be blocked if
this fault occurs ten times in a
row.
Press the electronics reset button. If this faults occurs repeat-
edly, notify customer support.
18
Pressure sensor,
heating circuit
The heating circuit pressure sen-
sor is not providing a plausible
signal.
19
Defrost duration of
cross-countercurrent
heat exchanger
Defrosting is not completed
after expiry of the defined time.
The fault is displayed until the
defrost process has been com-
pleted.
20
Solar sensor
The solar circuit pump is not
being switched.
The measured sensor values have
been constantly outside the permissi-
ble range for a specified period.
Check whether the solar sensor is connected or, if no solar
thermal system is connected, whether parameter “SOLAR ACTI-
VATION” is set to “OFF”.
Press the electronics reset button for one second. If this faults
occurs repeatedly, notify customer support.
21
Outside temperature
sensor
The heating system runs con-
stantly with the flow tempera-
ture for manual mode (param-
eter P10).
The measured sensor values have
been constantly outside the permissi-
ble range for a specified period.
Press the electronics reset button for one second. If this faults
occurs repeatedly, notify customer support.
22
Hot gas temperature
sensor
The compressor is switched off
at outside temperatures < –10 °C
and condenser temperatures
> 40 °C.
The measured sensor values have
been constantly outside the permissi-
ble range for a specified period.
Press the electronics reset button for one second. If this faults
occurs repeatedly, notify customer support.
23
Condenser tempera-
ture sensor
The compressor is stopped.
The measured sensor values have
been constantly outside the permissi-
ble range for a specified period.
Press the electronics reset button for one second. If this faults
occurs repeatedly, notify customer support.
24
Evaporator tempera-
ture sensor
The compressor is stopped.
The measured sensor values have
been constantly outside the permissi-
ble range for a specified period.
Press the electronics reset button for one second. If this faults
occurs repeatedly, notify customer support.
25
Compressor inlet
temperature
Cooling mode will be blocked.
The measured sensor values have
been constantly outside the permissi-
ble range for a specified period.
Press the electronics reset button for one second. If this faults
occurs repeatedly, notify customer support.
26
Return temperature
sensor in heating
circuit
The heating system switches
over to heating mode subject to
flow temperature. The amount of
solar heat cannot be calculated.
The measured sensor values have
been constantly outside the permissi-
ble range for a specified period.
Press the electronics reset button for one second. If this faults
occurs repeatedly, notify customer support.
27
Evaporator output
temperature
The heating mode heat pump
evaporator control is blocked.
The measured sensor values have
been constantly outside the permissi-
ble range for a specified period.
Press the electronics reset button for one second. If this faults
occurs repeatedly, notify customer support.
28
Flow temperature
sensor in heating
circuit
The heating system switches
over to heating mode subject to
return temperature. The electric
emergency/booster heater out-
put cannot be calculated.
The measured sensor values have
been constantly outside the permissi-
ble range for a specified period.
Press the electronics reset button for one second. If this faults
occurs repeatedly, notify customer support.
29
DHW temperature
sensor
DHW heating is blocked.
The measured sensor values have
been constantly outside the permissi-
ble range for a specified period.
Press the electronics reset button for one second. If this faults
occurs repeatedly, notify customer support.
30
Software version
Press the electronics reset button. If this faults occurs repeat-
edly, notify customer support. The software version does not
match the hardware version.
31 RAM
Press the electronics reset button. If this faults occurs repeat-
edly, notify customer support. Replace the control unit.