High Lockout
442 on Ideal Ideal Classic SE15P FF

Your boiler has experienced a nervous breakdown in its main computer brain, which means it cannot communicate with itself and has stopped working for safety.

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

internal failure - electronic

What causes this fault?

This fault occurs when the boiler's main control board suffers a hardware failure, preventing it from processing instructions or identifying its own components. The most common reason is age-related wear on the delicate electrical circuits or a sudden power surge that has damaged the board's memory.

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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