What does the Ferroli F4 fault code mean?

Your boiler has stopped working because it cannot safely confirm that waste gases are being cleared through the flue pipe.

How much does it cost to fix Ferroli error code F4?

Typical repair cost for the Ferroli F4 fault is £120-£350 including labour.

The air pressure switch is not making contact (contacts open). Check the fan, the venturi, the pressure switch and the flue.

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Six most common causes of dropping pressure.

Each noise points to a different fault.

Safety-critical — turn off, read this.