High Lockout
E01 on Vokera Pinnacle

Your boiler has tried to light but failed to start, 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

Ignition failure

What causes this fault?

This fault occurs when the boiler's control system attempts to start the burner but fails to detect a stable flame after several attempts. The most common reasons include a lack of gas reaching the unit, a dirty ignition probe that cannot create a spark, or a component failure that prevents the gas valve from opening.

In extremely cold weather, this error can be triggered by a frozen gas meter regulator or ice blocking the external flue terminal, both of which prevent the boiler from lighting safely.

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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