High Lockout
ON ON FLASH on Baxi Solo

Your boiler's internal computer has developed a fault and can no longer control the heating process 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

Printed circuit board (PCB) error

What causes this fault?

This fault occurs when the electrical components on the main control board suffer a critical failure, preventing the system from processing instructions correctly. The most common reason is general wear and tear over many years of use, though it can also be triggered by a sudden power surge or moisture getting into the casing.

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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