High
284 on Worcester Bosch Greenstar 8000 Style

Your boiler has detected an issue with the internal valve that mixes gas and air, which is preventing it from firing up correctly.

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

Opening air/gas ratio control valve/oil solenoid valves

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

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