High Lockout
F0279 on Worcester Bosch GB162

Your boiler's main internal computer has developed a serious internal fault and cannot safely manage the burner.

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

The burner control unit, or KIM, is faulty – control unit may need replacing

What causes this fault?

This fault occurs when the boiler's internal computer chips suffer a critical communication failure or hardware breakdown. It is typically caused by electrical wear over time or a sudden power surge that damages the delicate circuitry required to manage the burner safely.

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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