Medium Warning
Ad on Worcester Bosch Greenstar 30HE

Your boiler is unable to detect the temperature sensor for your hot water tank, which means it doesn't know when to heat your water.

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

Tank NTC sensor not detected.

What causes this fault?

This fault occurs when the connection between your boiler and your hot water cylinder is broken or interrupted. The most common reason is that the temperature probe attached to your water tank has failed, or the electrical wiring connecting that probe back to the boiler has become loose or damaged.

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 →A8View →

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