High
Fast flash on Worcester Bosch 24 RSF

Your boiler has detected a critical internal error with its electronics or air management system and has disabled itself for safety.

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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