High Lockout
460 on Ideal Ideal Classic SE15P FF

Your boiler's internal computer has encountered a critical 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 a hardware failure, meaning it can no longer send or receive instructions to vital components like the pump or gas valve. The most common reason is an electrical short-circuit or component degradation on the circuit board itself, which prevents the 'brain' of the boiler from functioning correctly.

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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