LED 4 (Flashing light) Low

Boiler Fault Code LED 4 (Flashing light)

Also written as LED4FLASHINGLIGHT — same fault.

Reviewed by the BoilerFaultCodes Editorial Team Last reviewed

Fault code LED 4 (Flashing light) appears across 1 boiler brand and 4 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 in standby mode and is working correctly, meaning it is simply waiting for a signal from your thermostat to start heating your home. (As reported on Ferroli Domina 102)

Pick your boiler brand for the LED 4 (Flashing light) fix

Ferroli LED 4 (Flashing light) 4 models

Source

Information for the LED 4 (Flashing light) 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