High Lockout
ON ON ON on Baxi Solo

Your boiler has detected an internal electrical communication problem between its main control components.

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

Low voltage wiring harness error

What causes this fault?

This fault occurs when the internal electrical signals between the boiler's control systems and the gas valve are interrupted or lost. The most common reason is a loose connection in the wiring or a degradation of the copper pins within the harness, which prevents the computer from safely controlling the boiler's 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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