High Lockout
E10 on Vokera Evolve

Your boiler has stopped working because it failed to light the flame after several attempts, usually due to a lack of gas supply or an ignition problem.

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

Flame lockout

What causes this fault?

This fault occurs when the boiler attempts to start up but cannot successfully establish or detect a steady flame. The most common reasons are a temporary interruption in the gas supply, a build-up of carbon on the ignition parts, or a component failure that prevents the spark from firing.

This issue can occur in freezing temperatures if the external gas regulator or pipework becomes restricted by extreme cold, though it is often a year-round mechanical fault.

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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