High Lockout
F67 on Glow-worm Flexicom hx

Your boiler's internal computer has encountered a critical communication error and can no longer control the heating system safely.

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

Main PCB fault

What causes this fault?

This fault occurs when the boiler's main control board suffers a hardware failure or a corruption of its internal memory. It is usually caused by electrical components wearing out over time or damage from a sudden power surge that disrupts the board's ability to process data.

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

F61View →F62View →F63View →F64View →

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