BoilerFaultCodes Fault 54 / 145 Low
Boiler Fault Code Fault 54 / 145
Also written as FAULT54145 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code Fault 54 / 145 appears across 1 boiler brand and 2 models. The exact meaning varies by manufacturer — pick your boiler brand below to see the model-specific fix.
Most common meaning Your boiler is warning you that your solar-heated water tank hasn't reached a high enough temperature to safely kill off any potential bacteria. (As reported on Worcester Bosch Greenstar CDi Compact)
Pick your boiler brand for the Fault 54 / 145 fix
Source
Information for the Fault 54 / 145 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