Boiler Fault Code LED 4

Also written as LED4 — same fault.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026

Fault code LED 4 appears across 3 boiler brands and 13 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 a temporary rest period to prevent the system from cycling on and off too rapidly, and it should restart automatically once a few minutes have passed. (As reported on Ferroli Domina 102)