High Lockout
FLASH ON FLASH on Baxi Solo

Your boiler's electronic control board has developed a fault, meaning the internal computer can no longer safely operate the heating system.

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 boiler's internal computer chips or electrical paths fail due to age, heat stress, or a sudden power surge. The most common reason is that the delicate components on the circuit board have worn out over time, causing the system to lose its ability to communicate with the rest of the boiler safely.

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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