High Lockout
E 17 on Vokera Hydra

Your boiler has detected an internal electronic error within its control brain, which means it has safely shut down to prevent incorrect operation.

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 experiences an internal hardware failure, meaning it can no longer process signals or safety checks correctly. The most common reason is general wear and tear of the electrical components on the circuit board over time, or damage caused by a power surge.

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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