Medium
A7 on Worcester Bosch 26 CDi Xtra

Your boiler's hot water sensor has failed or has a loose connection, meaning the system cannot accurately measure the temperature of the water coming out of your taps.

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

The hot water negative thermistor coefficient (NTC) sensor is defective – the hot water sensor or connecting leads need checking.

Engineer required

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

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Related fault codes

A8View →B1View →

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