225 High

Boiler Fault Code 225

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code 225 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 has detected that the water temperature is moving through the system unevenly, causing it to shut down to prevent damage. (As reported on Worcester Bosch Greenstar CDi Compact)

Pick your boiler brand for the 225 fix

Source

Information for the 225 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