High Lockout
FLASH ON ON on Baxi Solo

Your boiler's internal computer has developed an electrical fault and is unable to control the heating process.

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) fault

What causes this fault?

This fault occurs when the main control board's internal components or solder joints fail due to age, heat stress, or minor electrical surges. Because this part acts as the boiler's brain, any breakdown in its circuitry means it can no longer safely coordinate ignition or monitor safety sensors.

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.

Find a Gas Safe engineer
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