BoilerFaultCodes
Saunier Duval Boiler Fault Codes
502 fault codes across 20 Saunier Duval boiler models — explained in plain English.
French brand owned by Vaillant Group. Popular across Europe.
Just want the most common Saunier Duval problems?
The top 8 faults across the whole Saunier Duval range — causes, DIY checks, repair costs.
High-severity Saunier Duval fault codes
F1 F4 E01 E02 E03
Your boiler is attempting to start up, but it is unable to keep the flame alight once it ignites, so it safely shuts itself down.
Themaclassic F23E
Your boiler is attempting to start its flame but is unable to stay lit, causing it to shut down for safety reasons.
Themaclassic F23E
Your boiler is failing to light the flame properly, so it has turned itself off for safety until it is repaired.
Themaclassic F23E
Your boiler is struggling to clear exhaust gases safely, so it has turned itself off to prevent any risk.
Themaclassic F23E
Your boiler is failing to vent exhaust gases safely, so it has stopped working to prevent a hazard.
Themaclassic F23E
All models
20 Saunier Duval boiler models
Themaclassic F23E
Combi Discontinued
Themaclassic F25E
Combi Discontinued
Themaclassic Plus F30E
Combi Discontinued
Thelia 23E
Combi Discontinued
Isofast F28E
Combi Discontinued
Isomax F30E
Combi Discontinued
Ecosy 24E
Combi Discontinued
Opalia F24E
Combi Discontinued
Isotwin F30E
Combi Discontinued
SD 30e
Combi Discontinued
Isofast
Combi Discontinued
Sylva
Combi Discontinued
Xeon 120 FF
Regular Discontinued
Ecosy
Combi Discontinued
Enviroplus
Combi Discontinued
Opalia
Discontinued
Semia Condens F30 E
Combi Discontinued
Thelia
Combi Discontinued
Thema F 30 E Plus
Combi Discontinued
Xeon 30ff
System Discontinued