High
284 on Worcester Bosch Greenstar 28CDi

Your boiler is having difficulty communicating with the system that manages the essential mix of gas and air needed for safe ignition.

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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