High Lockout
79 on Vokera Easi-Heat 29

Your boiler has detected an internal communication error or a temporary processing fault that is preventing it from running properly.

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

Temporary fault code (Refer to section 7.10)

What causes this fault?

This fault occurs when the boiler's internal computer experiences a software glitch or loses communication with the sensors and valves it controls. The most common reason is a momentary power fluctuation or a breakdown in the wiring connections that prevents the main control board from processing data 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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Related fault codes

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