High
Fast flash on Worcester Bosch 30i Junior

Your boiler has experienced a serious internal communication error or hardware failure that has caused it to shut down 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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Related fault codes

C6View →A1View →

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