While you wait for answers, we may have found some information which could help you.
Click here for Help Leaks ShowersHow can I fix my Saunier Duval Semia Condens boiler?
Saunier Duval F35E auto-vents down to code 21 in minutes?
Saunier Duval Isofast condens F35E....nothing working?
saunier duval sd620f?
isotwin condens f 35 e service menu codes?
'f19' error report - Saunier Duval 'Thermoclassic' boiler?