Medium
3 flashes on Worcester Bosch Greenstar 25CDi

Your boiler's hot water temperature sensor has stopped working, which means the system cannot accurately heat your water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

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. Check hot water NTC sensor and connecting lead for circuit breaks/short circuits.

Engineer required

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

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