High Lockout
417 on Ideal Ideal Classic SE15P FF

Your boiler's computer control board has experienced an internal electrical fault and is unable to communicate with its components.

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 electronic failure that prevents it from processing instructions or monitoring safety sensors. The most common reason is the natural degradation of electrical components over time, though it can also be triggered by a sudden power surge or moisture getting onto the circuitry.

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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