BoilerFaultCodes.com
S.61 High Lockout

Your boiler has detected that its internal safety settings don't match the type of gas being supplied to the property, causing it to stop running for safety.

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: Fault: Incorrect gas type. The coding resistor on the PCB does not match the entered gas group (see also F.92).

What causes this fault?

This fault occurs when the boiler's internal computer detects a conflict between its hardware settings and the electronic signal from the gas valve. It is most commonly caused by incorrect programming during a part replacement or a technical failure in the main circuit board's ability to identify which type of gas it should be burning. Because the boiler cannot be sure it is burning fuel safely, it shuts down instantly as a protective measure.

Typical repair cost £120-450 (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

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