How much does it cost to fix Ferroli error code F40?

Typical repair cost for the Ferroli F40 fault is £80-150 including labour.

F40 High

Ferroli F40 Fault Code

Q: What does the Ferroli F40 fault code mean?

Your boiler has detected that the water pressure inside your heating system is dangerously high, causing it to shut down to prevent internal damage.

The Ferroli F40 fault code means: your boiler has detected that the water pressure inside your heating system is dangerously high, causing it to shut down to prevent internal damage.. It appears on 7 Ferroli models in our database.

Technical description: Incorrect system water pressure (Pressure too high above 3 - 5 bar)

Typical repair cost £80-150 (including labour)

DIY fix possible

Check that the silver filling loop valves are tightly closed.Bleed water from a radiator using a bleed key to reduce the pressure.Monitor the pressure gauge to ensure it returns to between 1 and 1.5 bar.Press the reset button once the pressure is stabilised.

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Ferroli models that show the F40 fault code

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

Source

Ferroli F40 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