BoilerFaultCodesYour boiler has failed to complete its initial setup process, meaning it hasn't properly cleared air from the system or finished its first startup sequence.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Installation in unfinished state - Boiler venting Fault in burner / Ignition valve
What causes this fault?
This fault occurs when the boiler's automatic commissioning program fails to complete, often because the system hasn't been fully bled of air during setup. It signifies that the internal sensors cannot confirm a stable flame or safe operating conditions, causing the computer to stop the sequence for safety. The root cause is usually a snag during the initial 'purging' phase or a component like the ignition electrode failing to spark correctly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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