LED2 flashing, LED3 on Medium

Boiler Fault Code LED2 flashing, LED3 on

Also written as LED2FLASHINGLED3ON — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code LED2 flashing, LED3 on appears across 1 boiler brand and 6 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 a sensor problem that is preventing it from providing hot water correctly. (As reported on Ideal Mini HE)

Pick your boiler brand for the LED2 flashing, LED3 on fix

Ideal LED2 flashing, LED3 on 6 models

Source

Information for the LED2 flashing, 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