LED3 on Low

Boiler Fault Code LED3 on

Also written as LED3ON — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code LED3 on 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 currently working to provide hot water to your taps, which is a normal operating signal rather than a fault. (As reported on Ferroli Modena F)

Pick your boiler brand for the LED3 on fix

Ferroli LED3 on 1 model

Source

Information for the LED3 on 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 7 July 2026