High Lockout
E44 on Vokera Pinnacle

Your boiler’s main computer brain has developed an internal electrical 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

Internal fault (PCB)

What causes this fault?

This fault occurs when the boiler's main control board suffers a critical internal electrical failure, meaning it can no longer communicate with the sensors or fire the burner safely. The most common reason is age-related wear on the board's circuitry or a small power surge that has damaged a sensitive component. Because the 'brain' of the boiler is compromised, it shuts down entirely to prevent any unpredictable behavior.

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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