BoilerFaultCodes Fault 41 / 103 Low
Boiler Fault Code Fault 41 / 103
Also written as FAULT41103 — same fault.
Reviewed by the BoilerFaultCodes Editorial Team Last reviewed
Fault code Fault 41 / 103 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 has detected an electrical problem with the sensor that measures the temperature at the bottom of your solar hot water cylinder. (As reported on Worcester Bosch Greenstar CDi Compact)
Pick your boiler brand for the Fault 41 / 103 fix
Source
Information for the Fault 41 / 103 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