BoilerFaultCodes.com
01 High Lockout

Your boiler has failed to light the gas burner, which means you will not have any heating or hot water at the moment.

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: Failure to ignite

What causes this fault?

This fault occurs when the boiler tries to light the gas three times but fails to detect a flame. The most common reasons are a disruption to your gas supply, a worn-out ignition spark, or a component failure that prevents the gas from flowing correctly into the burner.

This fault is slightly more common during the first cold snap of winter when components that have been sitting idle over summer are suddenly put under heavy strain.

Typical repair cost £120-£350 (including labour)

DIY fix possible

Check if other gas appliances, like a cooker, are working to ensure gas is reaching the property.Press the 'Reset' button and hold it for a few seconds to try and restart the ignition sequence.Verify that your gas meter has credit if you use a pre-payment meter.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

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Protect yourself from future repair bills

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