Code Faults Cause
of the
fault
Description Checking / solution
D09 DHW S.FAILURE
SCU Domestic hot water sensor fault
Remarks:
Heating of domestic hot water is no
longer ensured.
The load pump operates.
The load temperature of the dhw
tank is the same as the boiler.
Bad connection
4 Check whether the sensor is connected:
¼See chapter: "Deletion of sensors from
the memory in the PCB", page 79
4 Check the link and the connectors
4 Check that the sensor has been correctly fitted
Sensor fault
4 Check the Ohmic value of the sensor
4 Replace the sensor if necessary
D11
D12
D13
ROOM S.A FAIL.
ROOM S.B FAIL.
ROOM S.C FAIL.
SCU A room temperature sensor fault
B room temperature sensor fault
C room temperature sensor fault
Note:
The circuit concerned operates
without any influence from the
room sensor.
Bad connection
4 Check whether the sensor is connected:
¼See chapter: "Deletion of sensors from
the memory in the PCB", page 79
4 Check the link and the connectors
4 Check that the sensor has been correctly fitted
Sensor fault
4 Check the Ohmic value of the sensor
4 Replace the sensor if necessary
D14
MC COM.FAIL
SCU Communication failure between
the SCU PCB and the boiler radio
module
Bad connection
4 Check the link and the connectors
Boiler module failure
4 Change the boiler module
D15 ST.TANK S.FAIL
SCU Storage tank sensor fault
Note:
The hot water storage tank
reheating operation is no longer
assured.
Bad connection
4 Check whether the sensor is connected:
¼See chapter: "Deletion of sensors from
the memory in the PCB", page 79
4 Check the link and the connectors
4 Check that the sensor has been correctly fitted
Sensor fault
4 Check the Ohmic value of the sensor
4 Replace the sensor if necessary
D16
D16
SWIM.B S.FAIL
SWIM.C S.FAIL
SCU Swimming pool sensor fault circuit
B
Swimming pool sensor fault circuit
C
Note:
Swimming pool reheating is
always done during the circuit’s
comfort period.
Bad connection
4 Check whether the sensor is connected:
¼See chapter: "Deletion of sensors from
the memory in the PCB", page 79
4 Check the link and the connectors
4 Check that the sensor has been correctly fitted
Sensor fault
4 Check the Ohmic value of the sensor
4 Replace the sensor if necessary
Diematic iSystem For C 330 / C 630 ECO 7. Troubleshooting
31082018 - 7600691-001-06
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