DeDietrich MCA 15 User Manual page 36

6. Troubleshooting
Code Faults
L09 STB BACK
L10 DEP-RET<MIN
L11 DEP-RET>MAX
L12 STB OPEN
BURNER FAILURE PCU
L14
35
Cause Description
of the
fault
PCU Return temperature too high
PCU Difference between the flow and
return temperatures insufficient
PCU Difference between the flow and
return temperatures too great
PCU Maximum boiler temperature
exceeded (STB thermostat
maximum)
5 burner start-up failures
MCA 15 - MCA 25 MCA 25/28 MI
Checking / solution
Bad connection
Sensor fault
Contact the professional who takes care of
4
maintenance of the appliance
No water circulation
Vent the air in the heating system
4
Check the circulation (direction, pump,
4
valves)
Check the water pressure
4
Bad connection
Sensor fault
Contact the professional who takes care of
4
maintenance of the appliance
No water circulation
Vent the air in the heating system
4
Check the circulation (direction, pump,
4
valves)
Check the water pressure
4
Bad connection
Sensor fault
Contact the professional who takes care of
4
maintenance of the appliance
No water circulation
Vent the air in the heating system
4
Check the circulation (direction, pump,
4
valves)
Check the water pressure
4
Bad connection
Sensor fault
Contact the professional who takes care of
4
maintenance of the appliance
No water circulation
Vent the air in the heating system
4
Check the circulation (direction, pump,
4
valves)
Check the water pressure
4
No ignition
Contact the professional who takes care of
4
maintenance of the appliance
Presence of the ignition arc but no flame formation
Check that the gas valve is fully opened
4
Contact the professional who takes care of
4
maintenance of the appliance
Presence of the flame but insufficient ionization
(<3 µA)
Check that the gas valve is fully opened
4
Contact the professional who takes care of
4
maintenance of the appliance
23/08/2011 - 300024159-001-B