Medium
275 on Worcester Bosch Greenstar 8000

Your boiler is currently stuck in a diagnostic testing mode rather than operating normally to provide heating or hot water.

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 electronics in test mode

Engineer required

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

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