Manual
Code Messages Description Checking / solution
B28 BL.BAD.CONFIG
An HL tank is detected whilst the
boiler cannot control it.
This message disappears after
10 seconds if the boiler can control
the HL tank
4 Wait for 10 seconds to see whether the error
persists
4 Contact the professional who takes care of
maintenance of the appliance
B29 to
B34
BL.UNKNOWN Bxx
Incorrect configuration of the PCU
4 Contact the professional who takes care of
maintenance of the appliance.
M08 REVISION AUTO
An automatic service is requested The date programmed for the service has been
reached.
4 If the symbol ? flashes, press key ?. The
installer’s contact details are displayed.
4 Contact the professional who takes care of
maintenance of the appliance.
M23 CHANGE OUTSI.S
The outside temperature sensor is
defective.
4 Contact the professional who takes care of
maintenance of the appliance.
M30 BL.SYSTEM NETWORK
No communication with the master
regulation through the MODBUS
network
4 Contact the professional who takes care of
maintenance of the appliance
M31 BL.COM.MODBUS
Incorrect configuration of the
MODBUS network
4 Contact the professional who takes care of
maintenance of the appliance
6.3 Faults (Code type Lxx or Dxx)
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:
bar
1
1
2
2
r
c
STD
(
t
v
0 2 4 6 8 10 12 14 16 18 22 2420
p
b
AUTO
x
c
r
j
M
g
m
SUNDAY 11:45
TEMP. : 68°
PCU. COM. FAIL. D27
C002604-B-04
bar
1
1
2
2
r
c
STD
(
'
t
v
0 2 4 6 8 10 12 14 16 18 22 2420
p
b
AUTO
x
c
r
j
M
g
m
SUNDAY 11:45
TEMP. : 68°
PCU COM.FAIL D27
C002302-D-04
6. Troubleshooting AFC 18 - AFC 24 - AFC 30
33
09/01/2014 - 300026440-001-03