High Lockout
F10 on Ferroli Modena HE

Your boiler's internal sensor that monitors the temperature of water leaving the unit has stopped working correctly, and the system has shut down to prevent overheating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Flow sensor error – sensor damaged, short circuited, sensor damaged or wiring broken

What causes this fault?

This fault occurs when the boiler's control board loses communication with the temperature sensor attached to the main heating pipe. The most common reason is that the internal sensor has physically degraded and failed, or the electrical wires connecting it to the main computer have become loose or damaged.

Engineer required

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

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Related fault codes

F11View →F14View →A03View →

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