High Lockout
2950 B on Worcester Bosch Greenstar 8000 Life/Style

Your boiler is trying to light itself but cannot detect a flame, meaning your heating and hot water will likely stop working.

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 flame signal. Following starting procedure the burner starts automatically. After cleaning set the correct gas / air ratio correctly

What causes this fault?

This fault occurs when the boiler's internal computer tries to start the combustion process but cannot confirm that a flame has actually been lit. The most common reasons are a build-up of carbon on the sensing probes or a component failure that prevents gas from flowing correctly into the burner.

This fault is more common during the first few cold spells of autumn, as components that have been idle over summer can struggle to operate or may have become blocked by debris.

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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