BoilerFaultCodes 311 High
Boiler Fault Code 311
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 311 appears across 1 boiler brand and 2 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler's electronic control unit has identified an internal software or configuration error that has caused it to lock itself to prevent damage. (As reported on Worcester Bosch Greenstar CDi Compact)
Pick your boiler brand for the 311 fix
Source
Information for the 311 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