BoilerFaultCodes 612 High
Boiler Fault Code 612
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 612 appears across 1 boiler brand and 1 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler's fan is not spinning at the correct speed, which prevents the unit from starting up safely for heating or hot water. (As reported on Ariston Alteas One)
Pick your boiler brand for the 612 fix
Source
Information for the 612 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