High Lockout
417 on Ideal Response SE

Your boiler's internal computer brain has developed an electrical fault and can no longer control the heating 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 control center suffers a critical communication failure between its components. It is most commonly caused by wear and tear on the electrical circuitry or a sudden power surge that has damaged the sensitive microprocessors inside 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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