BoilerFaultCodes.com
E1-65 High Lockout

Your boiler's internal electronic self-monitoring system has detected a technical fault and has shut down 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: Internal SCOT system error. Perform reset if needed

What causes this fault?

This fault occurs when the boiler's internal computer system fails to communicate correctly with the safety controls that monitor the gas flame. It is usually triggered by a communication error on the circuit board or a failure in the electronic calibration system that ensures the boiler is burning gas safely. Because the boiler cannot verify that the combustion process is stable, it will shut down to prevent incorrect gas mixtures.

Typical repair cost £150-450 (including labour)

DIY fix possible

Locate the Power/Reset button on the front control panelPress and hold the Reset button for 2 secondsWait for the boiler to complete its restart sequence to see if the central heating resumes

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