Medium
A5 on Worcester Bosch Ri 25 HE

Your boiler is struggling to accurately detect the temperature of the water used for your heating and hot water, which may cause it to stop working correctly as a precaution.

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

Heat store NTC sensor 2 defective

Engineer required

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

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