Ferroli Green LED on Fault Code
Also written as GREENLEDON — same fault.
The Ferroli Green LED on fault code means: your boiler is receiving power and is ready to work, but it hasn't been told to turn on the heating or hot water yet.. It appears on 2 Ferroli models in our database.
Technical description: Boiler is on but there is no heat demand
DIY fix possible
Check that your room thermostat is turned up higher than the current room temperature.Ensure your programmer or heating timer is set to 'ON'.Turn on a hot water tap to see if the boiler fires up for water demand.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Ferroli models that show the Green LED on fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ferroli Green LED 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 27 April 2026