High
F6 on Ferroli Tempra 12 18

Your boiler has lost the ability to read the temperature of the water being sent to your radiators, so it has shut down as a precaution 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

Central heating flow temperature sensor fault (open circuit or short circuit). Check the sensor and its wiring.

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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