BoilerFaultCodes S.26 Medium
Boiler Fault Code S.26
Also written as S26 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code S.26 appears across 4 boiler brands and 74 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler is staying in a cooling-down mode because the internal fan is running for longer than it should after heating your water. (As reported on Vaillant ecoMAX 613)
Pick your boiler brand for the S.26 fix
Source
Information for the S.26 fault code is sourced from the official service / installation manual for each model that displays it. Read more about how we source fault codes →
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026