High
FAULT POINT D on Worcester Bosch Greenstar 15sbi

Your boiler has detected a critical internal error and has safely shut itself down to prevent damage, meaning your heating and hot water will not work until it is reset or repaired.

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.

Technical description

Lockout light on constantly (on or off if burner light is off)

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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