BoilerFaultCodes.com
2957 High Lockout

Your boiler has detected an internal electrical communication error, which means it has stopped working as a safety precaution.

Call an engineer soon

Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Boiler electr. system fault

What causes this fault?

This fault occurs when the boiler's internal computer is unable to communicate with its electrical components, effectively causing the system to lose its 'train of thought'. The most common reason is a hardware failure within the main circuit board or a loose connection in the wiring that links the various sensors together. Because the boiler can no longer verify that it is operating safely, it shuts down immediately to prevent damage.

Typical repair cost £280-550 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Protect yourself from future repair bills

A boiler cover plan would cover faults like 2957 — no call-out fees, no surprises.

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