High
Fast flash on Worcester Bosch Greenstar i Junior

Your boiler has detected a critical internal error that caused it to shut down for safety reasons and will not restart on its own.

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

Volatile lockout (sensor, fan or code plug)

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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