8.3
Faults (Code type Lxx or Dxx)
In the event of operational failure, the control panel flashes and
displays an error message and a corresponding code.
1. Make a note of the code displayed.
The code is important for the correct and rapid diagnosis of the
type of failure and for any technical assistance that may be
needed.
2. Press the
t
key. If the code is displayed again, switch off the boiler
and then switch it back on.
3. Press the
?
key. Follow the instructions displayed to solve the
problem.
4. Consult the meaning of the codes in the table below:
Faults
Code Cause
of the
error
Description
Checking / solution
PSU FAIL
L00
PCU
PSU PCB not connected
Bad connection
4
Check the wiring between the PCU and PSU PCBs
PSU PCB faulty
4
Replace the PSU PCB
PSU PARAM FAIL
L01
PCU
The safety parameters are
incorrect
Bad connection
4
Check the wiring between the PCU and PSU PCBs
PSU PCB faulty
4
Replace the PSU PCB
DEF.OUTLET S.
L02
PCU
The boiler flow sensor has
short-circuited
Bad connection
4
Check the wiring between the PCU PCB and the
sensor
4
Check that the SU PCB is correctly in place
4
Check that the sensor has been correctly fitted
Sensor fault
4
Check the Ohmic value of the sensor
4
Replace the sensor if necessary
bar
1
1
2
2
r
c
STD
(
t
v
0
2
4
6
8
10
12
14
16
18
22
24
20
p
b
AUTO
x c
r
j
M
g
m
SUNDAY 11:45
TEMP. : 68°
PCU. KOM. DEF D27
C002604-A-04
bar
1
1
2
2
r
c
STD
(
'
t
v
0
2
4
6
8
10
12
14
16
18
22
24
20
p
b
AUTO
x c
r
j
M
g
m
SUNDAY 11:45
TEMP. : 68°
PCU COM.FAIL D27
C002302-D-04
MCA 15 - MCA 25 MCA 25/28 MI
8. Troubleshooting
29/04/2010 - 300022146-001-B
115
