DE DIETRICH MODULENS AGC 15, AGC 25, AGC 35 - Manual (Page 33)

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 6. Troubleshooting
03/12/2013 - 300026080-001-03 32