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 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 currently working exactly as it should, indicating that it is actively heating water for your taps and shower. (As reported on Ferroli Modena HE)

Pick your boiler brand for the LED3 on fix

Ferroli LED3 on 2 models

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 27 April 2026