BoilerFaultCodes B02 High
Boiler Fault Code B02
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code B02 appears across 1 boiler brand and 6 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler is not receiving a signal from your thermostat, which means your heating won't turn on even if you try to increase the temperature. (As reported on Ariston Euro Combi 30 MFFI)
Pick your boiler brand for the B02 fix
Source
Information for the B02 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