Medium
3 flashes on Worcester Bosch Greenstar 35 CDi

Your boiler's temperature sensor for hot water has stopped working correctly, meaning your taps might not get warm.

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

Hot water NTC sensor defective.

Engineer required

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

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