High
LOCKOUT on Worcester Bosch Greenstar 27CDi

Your boiler has stopped working because it cannot safely ignite or maintain its internal flame.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

What the manual says

Manufacturer manual

General burner lockout condition requiring investigation of pulsation, electrical connections, flame detection, or fuel supply

From this model's manual
Verified against the Worcester Bosch Greenstar 27cdi installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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