High Lockout
441 on Ideal Ideal Classic SE15P FF

Your boiler's internal computer brain has developed a terminal electronic glitch 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

internal failure - electronic

What causes this fault?

This fault occurs when the boiler's main control board suffers a critical hardware failure, meaning it can no longer process data or send signals to other components. The most common reasons for this are electrical surges that damage the delicate circuitry or general wear and tear on the board's capacitors over time. Because the 'brain' of the boiler is essentially broken, it can no longer guarantee safe 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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