Medium
232 on Worcester Bosch Greenstar 28CDi

Your boiler has been told to stop running by an external device, such as a smart thermostat or a frost protection controller.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Boiler locked by external switching contact

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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