Medium
1021 on Worcester Bosch Greenstar 8000 Style

Your boiler is struggling to accurately measure the temperature of the water being heated for your taps and shower, so it has stopped heating it to prevent overheating.

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

Cylinder charging or hot water temperature sensor faulty

Engineer required

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

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