We may have found other answers which could help you.
Click here for Heating Boiler Ferolli
Ferolli Optimax HE 31C expansion vessel change?
F40 fault?
ferroli plus 31c has a code b2 any ideas?
i have a ferroli combi boiler i have 1/2 the radiators working and 1/2 not ?
Ferroli Optimax HE31c a26 problem?
Replace a diverter valve?