High Lockout
Burner on neon NOT illuminated on Potterton Performa 30 HE

Your boiler is not attempting to light the flame, which means you have no heating or hot water because the system has encountered an internal startup error.

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

Go to section 'F'

What causes this fault?

This fault occurs when the boiler's internal computer tries to start the ignition process but stops because it cannot detect a flame or verify that the gas is flowing correctly. The most common reason is an aging electronic component or a sensing probe that has become worn or dirty over time. Because the system cannot guarantee it is safe to stay lit, it prevents the burner from firing entirely to protect your home.

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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