Fault
Fault
code
Faulty mains fre-
35
quency
Pressure switch con-
37
tact open
39
External probe fault
No +/-1°C variation of
41
flow sensor
Protection for tempe-
rature difference >
42
21° between flow
sensor and safety
sensor
Cascade tempera-
50
ture sensor fault
Protection for tempe-
rature difference >
52
18° between flow
sensor and safety
sensor
61
Controller fault
No communication
62
between controller
and gas valve
63
64
Controller fault
65
66
No communication
99
between controller
and display
182
Possible cause
Electric mains trouble
Low system pressure
Probe damaged or wiring shorted
Probe disconnected after activating the sliding
temperature
Flow sensor disconnected from pipe
Insufficient circulation in boiler
Incorrect flow sensor position
Sensor damaged
Wiring shorted
Wiring disconnected
Insufficient circulation in boiler
Controller internal error
Controller not connected
Valve damaged
Controller internal error
Wiring disconnected
cod. 3541R963 - Rev. 00 - 09/2021
OPERA
Cure
Check the electrical system
Check the system water pressure
Check the wiring or replace the sensor
Reconnect the external probe or disable the
sliding temperature
Check the correct positioning and operation of
flow sensor
Check boiler/system water circulation
Check the integrity of sensor
Check the wiring or replace the sensor
Check boiler/system water circulation
Check the integrity of flow and safety sensor
Check the ground connection and replace the
controller if necessary.
Connect the controller to the gas valve
Replace the valve
Check the ground connection and replace the
controller if necessary
Check the wiring of the 6 wires between con-
troller and display
EN