High Lockout
E 06 on Vokera Hydra

Your boiler's internal computer has flagged a critical error that prevents it from starting up or operating 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 hardware failure, preventing it from processing instructions or communicating with internal sensors. It is usually caused by age-related component wear or an electrical surge that has damaged the delicate circuitry on the board.

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

E 02View →

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