Medium
A5 on Worcester Bosch ZB 7 27 HE

Your boiler is having trouble measuring the temperature of the internal hot water storage, which may prevent it from providing hot water correctly.

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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Related fault codes

A7View →

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