DE DIETRICH INNOVENS MCA 35 User Manual
Page 36
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Code Faults
Cause
of the
fault
Description
Checking / solution
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
DEP-RET
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
L14
BURNER FAILURE
PCU
5 burner start-up failures
No ignition
4
Contact the professional who takes care of
maintenance of the appliance
Presence of the ignition arc but no flame formation
4
Check that the gas valve is fully opened
4
Contact the professional who takes care of
maintenance of the appliance
Presence of the flame but insufficient ionization
(<3 µA)
4
Check that the gas valve is fully opened
4
Contact the professional who takes care of
maintenance of the appliance
6. Troubleshooting
MCA 35
35
24/08/2011 - 300024162-001-B