High Lockout
407 on Ideal Response SE

Your boiler's internal computer has suffered a technical failure and is unable to control the heating or hot water operations.

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 centre, known as the PCB, experiences a critical hardware failure or a communication breakdown between its internal components. The most common reason is an electrical short or component degradation on the circuit board itself, preventing it from safely managing the boiler's functions. In some cases, loose or damaged internal wiring can also disrupt the signals required for the system to operate.

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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