BoilerFaultCodes F0 338 High
Boiler Fault Code F0 338
Also written as F0338 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code F0 338 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 is repeatedly trying to start but failing because it cannot sense the water flowing through the system properly. (As reported on Worcester Bosch Greenstar 12i System)
Pick your boiler brand for the F0 338 fix
Source
Information for the F0 338 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