Emergency
Incorrect CO2 on Worcester Bosch Greenstar Utility

Your boiler is struggling to mix the correct amount of air and fuel during the combustion process, which could lead to unsafe fumes.

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 adjustment fault; Oil pressure incorrect

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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