Emergency
HIGH SMOKE NUMBER on Worcester Bosch Greenstar 27CDi

Your boiler is not burning fuel correctly, which is causing soot buildup and potential safety issues with the exhaust gases.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Act immediately

Turn off your boiler and stop using gas appliances. Call a Gas Safe engineer now. This fault can be dangerous if ignored.

Technical description

Air intake/flue blocked; Incorrect combustion settings; Oil pressure incorrect; Incorrect components used on combustion head; Faulty nozzle

Engineer required

This is a emergency severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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