High Lockout
411 on Ideal Ideal Classic SE15P FF

Your boiler's internal computer has encountered a critical electronic error and can no longer communicate with the rest of the system.

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 an internal hardware failure, essentially acting like a crashed computer that can no longer process instructions. The most common reason is electrical degradation of the board's components or a communication break in the internal wiring that prevents the system from running safely.

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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