DE DIETRICH INNOVENS MCA 25_28 BIC - Manual (Page 38)

Code Faults Cause
of the
fault Description Checking / solution
L16 PARASIT FLAME PCU Detection of a parasite flame Ionization current present when there should not
be a flame
Ignition transformer defective
Gas valve defective
The burner remains very hot: CO
2
too high
4
Contact the professional who takes care of
maintenance of the appliance
L17 VALVE FAIL PCU Problem on the gas valve Bad connection
SU PCB faulty
4 Contact the professional who takes care of
maintenance of the appliance
L34 FAN FAILURE PCU The fan is not running at the right
speed
Bad connection
Fan defective
4
Contact the professional who takes care of
maintenance of the appliance
L35 BACK>BOIL FAIL PCU Flow and return reversed Bad connection
Sensor fault
4
Contact the professional who takes care of
maintenance of the appliance
Water circulation direction reversed
4 Check the circulation (direction, pump,
valves)
L36 I-CURRENT FAIL PCU The flame went out more than 5
times in 24 hours while the burner
was operating
No ionization current
4 Check that the gas valve is fully opened
4
Contact the professional who takes care of
maintenance of the appliance
L37 SU COM.FAIL PCU Communication failure with the SU
PCB
Bad connection
4
Contact the professional who takes care of
maintenance of the appliance
L38 PCU COM.FAIL PCU Communication failure between the
PCU and SCU PCBs
Bad connection
SCU PCB not connected or faulty
4 Contact the professional who takes care of
maintenance of the appliance
L39 BL OPEN FAIL PCU The BL inlet opened for a short time Bad connection
External cause
Parameter incorrectly set
4
Contact the professional who takes care of
maintenance of the appliance
L40 TEST.HRU.FAIL PCU HRU/URC unit test error Bad connection
External cause
Parameter incorrectly set
4
Contact the professional who takes care of
maintenance of the appliance
L250 DEF.WATER MIS. PCU The water pressure is too low Hydraulic circuit incorrectly vented
Water leak
Measurement error
4 Top up with more water if necessary
4
Reset the boiler
L251 MANOMETRE FAIL PCU Fault on the water pressure sensor Wiring problem
The manometer is defective
Sensor pcb defective
4
Contact the professional who takes care of
maintenance of the appliance
6. Troubleshooting MCA 25/28 BIC
37 31/08/2011 - 300024163-001-B