High Lockout
413 on Ideal Ideal Classic SE15P FF

Your boiler’s internal control computer has encountered a critical electrical error and can no longer manage the system 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 central control board suffers a hardware malfunction or a breakdown in its internal electrical pathways. It is usually caused by natural component aging, though it can also be triggered by moisture ingress or a sudden electrical surge that damages the sensitive microprocessors.

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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