BoilerFaultCodes 4F High
Boiler Fault Code 4F
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code 4F 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 reached an unsafely high temperature and has shut down to prevent damage or overheating. (As reported on Ideal Maximiser SE)
Pick your boiler brand for the 4F fix
Source
Information for the 4F 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