DeDietrich AGC 10, User Manual

Page: 35 / 48

Code Faults Cause
of the
fault Description Checking / solution
L07 BACK S.FAILURE
PCU The return temperature sensor is on
an open circuit
Bad connection
Sensor fault
4
Contact the professional who takes care of
maintenance of the appliance
L08 BACK S.FAILURE
PCU Return temperature too low Bad connection
Sensor fault
4
Contact the professional who takes care of
maintenance of the appliance
No water circulation
4
Vent the air in the heating system
4
Check the circulation (direction, pump,
valves)
4
Check the water pressure
L09 STB BACK
PCU Return temperature too high Bad connection
Sensor fault
4
Contact the professional who takes care of
maintenance of the appliance
No water circulation
4
Vent the air in the heating system
4
Check the circulation (direction, pump,
valves)
4
Check the water pressure
L10 DT RET-DEP>MAX
PCU Difference between the flow and
return temperatures insufficient
Bad connection
Sensor fault
4
Contact the professional who takes care of
maintenance of the appliance
No water circulation
4
Vent the air in the heating system
4
Check the circulation (direction, pump,
valves)
4
Check the water pressure
L11 DEP-RET>MAX
PCU Difference between the flow and
return temperatures too great
Bad connection
Sensor fault
4
Contact the professional who takes care of
maintenance of the appliance
No water circulation
4
Vent the air in the heating system
4
Check the circulation (direction, pump,
valves)
4
Check the water pressure
L12 STB OPEN
PCU Maximum boiler temperature
exceeded (STB thermostat
maximum)
Bad connection
Sensor fault
4
Contact the professional who takes care of
maintenance of the appliance
No water circulation
4
Vent the air in the heating system
4
Check the circulation (direction, pump,
valves)
4
Check the water pressure
AGC 10/15 AGC 15 AGC 25 AGC 35 7. Troubleshooting
15/03/2016 - 300026080-001-07 34