BoilerFaultCodes F1259 High
Boiler Fault Code F1259
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code F1259 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 main internal computer or its configuration module has developed a communication failure, preventing the system from operating safely. (As reported on Worcester Bosch CDi Classic)
Pick your boiler brand for the F1259 fix
Source
Information for the F1259 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