High Lockout
51 on Vokera Easi-Heat 29

Your boiler's internal computer has encountered a memory or software error that prevents it from running 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

What causes this fault?

This fault occurs when the boiler's main control board experiences a software failure or a physical breakdown in its memory storage. It is often caused by electrical surges or internal wear and tear that prevents the computer from reading its own safety settings correctly.

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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