High
284 on Worcester Bosch Greenstar 12i System

Your boiler is struggling to ignite the flame reliably, meaning it cannot start the heating cycle.

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

Gas valve(s) opened, flame must be detected within safety time. The boiler prepares for a burner start. The gas valve is being controlled.

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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