Ferroli LED 4 (Flashing light) Fault Code
Also written as LED4FLASHINGLIGHT — same fault.
The Ferroli LED 4 (Flashing light) fault code means: 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.. It appears on 4 Ferroli models in our database.
Technical description: Central heating stand-by
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Ferroli models that show the LED 4 (Flashing light) fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ferroli LED 4 (Flashing light) fault code information on this page is sourced and cross-checked against the official Ferroli service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026