While you wait for answers, we may have found some information which could help you.
Click here for Saunier Duval IgniteSaunier Duval timeclock not working?
saunier Duval is over pressurising when the heating is on. ?
How can I fix my Saunier Duval Semia Condens boiler?
saunier duval boiler problem?
saunier duval sd620f?
Saunier Duval Isofast condens F35E....nothing working?