High Lockout
E 11 on Vokera Hydra

Your boiler's internal electronic brain has encountered a serious error and is unable to operate safely, causing the system to shut down.

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 electronic failure or a loss of communication between internal components. It is often caused by a voltage surge in the mains electricity or by moisture getting onto the circuitry, which prevents the board from safely managing the boiler's functions.

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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