High Lockout
406 on Ideal Ideal Classic SE15P FF

Your boiler's internal computer brain has developed an electrical fault and is unable to communicate with its own sensors.

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 central control board suffers a critical internal electrical failure. It is usually caused by a component on the board burning out or a short circuit in the wiring harness that prevents the brain from sending signals to the rest of the unit.

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

4 01View →4 05View →4 07View →

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