How much does it cost to fix boiler error code S.02?

Typical repair cost for the boiler S.02 fault is £0-80 including labour.

S.02 Low

Boiler Fault Code S.02

Also written as S02 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed 27 April 2026

Fault code S.02 appears across 4 boiler brands and 56 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.

Most common meaning Your boiler is currently preparing for heating by circulating water, but it has not yet fired the burner to create heat. (As reported on Vaillant ecoTEC Pro / ecoTEC Plus)

Pick your boiler brand for the S.02 fix

Ariston S.02 5 models Glow-worm S.02 12 models Heatline S.02 8 models Vaillant S.02 31 models

Source

Information for the S.02 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 27 April 2026