High Lockout
F67 on Ferroli BlueHelix Pro 25C

Your boiler's computer or main control board has experienced a hardware error and cannot communicate with the rest of the system.

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

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What causes this fault?

This fault occurs when the boiler's internal computer experiences a critical communication failure or hardware crash. It is usually caused by an electrical component on the control board wearing out over time or a loose connection in the internal wiring preventing signals from traveling correctly.

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

F43View →A61View →

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