Emergency
E01 on Worcester Bosch Greenstar 12i System

Your boiler has detected a problem with its internal ignition process and has shut down for safety to prevent a gas build-up.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

No technical description available in the provided text; only listed as 'Built-in fault finding diagnostics' as a feature.

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

EAView →E9View →

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