High Lockout
09 on Vokera Linea 28

Your boiler's internal computer has developed an error and can no longer control the heating system correctly.

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

PCB fault

What causes this fault?

This fault occurs when the boiler's main control board suffers an internal electronic failure or loses communication with the rest of the components. The most common reasons are age-related wear to the board's circuitry or a sudden electrical surge that has damaged the sensitive microprocessors.

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

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