LED3 on Low

Ferroli LED3 on Fault Code

Also written as LED3ON — same fault.

The Ferroli LED3 on fault code means: your boiler is currently working to provide hot water to your taps, which is a normal operating signal rather than a fault.. It appears on 1 Ferroli model in our database.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description: Domestic hot water circuit on

DIY fix possible

Check if any hot water taps are slightly open or drippingEnsure your shower or bath mixer is fully turned offMonitor the light to see if it turns off once you stop using hot water

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Ferroli models that show the LED3 on fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Ferroli LED3 on 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 7 July 2026