BoilerFaultCodes.com
A06 High Lockout

Your boiler is failing to stay lit after it tries to start up, meaning it cannot provide you with heating or hot water.

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: No flame after the ignition phase

What causes this fault?

This fault occurs when the boiler successfully creates a spark and ignites the gas, but then fails to detect that the flame is actually burning. The most common reasons are a dirty or worn-out detection sensor that can't 'see' the fire, or a faulty gas valve that isn't providing a steady enough flow of fuel to keep the flame stable.

Typical repair cost £120-350 (including labour)

DIY fix possible

Check that your gas supply is turned on at the meterCheck if other gas appliances, like a hob, are working correctlyReset the boiler by pressing the 'Reset' button for 1 second

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