How much does it cost to fix Ferroli error code F09 – A09?

Typical repair cost for the Ferroli F09 – A09 fault is £120-300 including labour.

F09 – A09 High

Ferroli F09 – A09 Fault Code

Q: What does the Ferroli F09 – A09 fault code mean?

Your boiler has shut down because it has detected it is getting too hot and has locked out for safety.

Also written as F09A09 — same fault.

The Ferroli F09 – A09 fault code means: your boiler has shut down because it has detected it is getting too hot and has locked out for safety.. It appears on 3 Ferroli models in our database.

Technical description: Overtemperature protection intervention

Typical repair cost £120-300 (including labour)

DIY fix possible

Check that all radiator valves are fully open to allow water to circulateEnsure there is enough water pressure indicated on the boiler gauge (usually 1.0 to 1.5 bar)Attempt to reset the boiler using the control knob or button

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Ferroli models that show the F09 – A09 fault code

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

Source

Ferroli F09 – A09 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