F74 High

Boiler Fault Code F74

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code F74 appears across 2 boiler brands 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 has lost the ability to monitor its own water pressure, meaning it has shut down as a safety precaution. (As reported on Glow-worm Flexicom 18sx)

Pick your boiler brand for the F74 fix

Source

Information for the F74 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