BoilerFaultCodes 224 / E9 High
Boiler Fault Code 224 / E9
Also written as 224E9 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 224 / E9 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 it has become too hot and has automatically switched itself off to prevent any damage to the unit. (As reported on Worcester Bosch Greenstar CDi Compact)
Pick your boiler brand for the 224 / E9 fix
Source
Information for the 224 / E9 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