Fer FERSYSTEM TECH 31 C Instructions For Use, Installation And Maintenance page 30

Fault
F12
DHW sensor fault
F13
Flue sensor fault
F14
Flow sensor fault
F15
Fan problem
F34
Supply voltage under 170V.
F35
Irregular mains frequency
F37
Incorrect system water pressure
F39
External probe fault
F42
Flow sensor fault
30
FERSYSTEM TECH 31 C
Possible cause
Sensor damaged
Wiring shorted
Wiring disconnected
Sensor damaged or wiring shorted
Sensor damaged or wiring broken
Sensor damaged or short circuited
Sensor damaged or wiring broken
Tachometer signal interrupted, fan
connection
Fan damaged, debris in fan
Electric supply problem
Electric supply problem
Pressure too low
Sensor damaged
Sensor damaged or short-circuited
Sensor damaged
Cod. 3540U320 - 09/2009 (Rev. 00)
Cure
Check the wiring or replace the sensor
Check the wiring or change the sensor
Check the wiring or change the
sensor
Check the wiring or change the sensor
Check the wiring or change the sensor
Check the wiring and fan
Check the fan, clean debris
Check the electrical system
Check the electrical system
Fill the system
Check the sensor
Check the wiring or change the sensor
Change the sensor