BoilerFaultCodes 356 High
Boiler Fault Code 356
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 356 appears across 1 boiler brand and 17 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 enough electrical power from the main supply to operate safely and has shut down as a precaution. (As reported on Worcester Bosch CDi Classic)
Pick your boiler brand for the 356 fix
Source
Information for the 356 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