High Lockout
A01 on Ferroli BlueHelix Pro 25C

Your boiler has failed to light the flame, which means you currently have no heating or hot water.

Call an engineer soon

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

Technical description

No burner ignition

What causes this fault?

This fault occurs when the boiler attempts to start up but cannot confirm that a flame has been established. The most common reasons are a lack of gas reaching the burner, a worn-out ignition spark, or a sensor failing to detect the heat even if the flame did briefly light.

This issue can occur during extreme cold snaps if the external gas regulator or meter freezes, restricting the flow of gas to the property.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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