High Lockout
8x on Vokera Easi-Heat 29

Your boiler's main internal computer has developed a malfunction and can no longer control the heating system 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

PCB fault

What causes this fault?

This fault occurs when the boiler's central control board suffers an internal hardware failure or a memory error, preventing it from processing safety data. The most common reasons are electrical surges, moisture ingress from a small internal leak, or simply the natural degradation of electrical components over time. Because the board can no longer communicate with the boiler's sensors, it shuts down the system entirely to prevent an unsafe operation.

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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