DeDietrich Innovens MCA 35 Installation And Service Manual page 112

8. Troubleshooting
Code Faults
L08 BACK S.FAILURE
L09 STB BACK
L10 DEP-RET>MAX
110
Cause Description
of the
fault
PCU Return temperature too low
PCU Return temperature too high
PCU Difference between the flow
and return temperatures
insufficient
Checking / solution
Bad connection
Check the wiring between the PCU PCB and the
4
sensor
Check that the SU PCB is correctly in place
4
Check that the sensor has been correctly fitted
4
Sensor fault
Check the Ohmic value of the sensor
4
Replace the sensor if necessary
4
No water circulation
Vent the air in the heating system
4
Check the circulation (direction, pump, valves)
4
Check the water pressure
4
Check the cleanliness of the heat exchanger
4
Bad connection
Check the wiring between the PCU PCB and the
4
sensor
Check that the SU PCB is correctly in place
4
Check that the sensor has been correctly fitted
4
Sensor fault
Check the Ohmic value of the sensor
4
Replace the sensor if necessary
4
No water circulation
Vent the air in the heating system
4
Check the circulation (direction, pump, valves)
4
Check the water pressure
4
Check the cleanliness of the heat exchanger
4
Sensor fault
Check the Ohmic value of the sensor
4
Replace the sensor if necessary
4
Bad connection
Check that the sensor has been correctly fitted
4
No water circulation
Vent the air in the heating system
4
Check the circulation (direction, pump, valves)
4
Check the water pressure
4
Check the cleanliness of the heat exchanger
4
Check that the heating pump is operating correctly
4
MCA 35
15/06/12 - 300022160-001-01