Medium
Ad on Worcester Bosch 537i

Your boiler is struggling to communicate with the temperature sensor on your hot water tank, which may prevent your water from heating up 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

Cylinder NTC sensor not detected.

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 →E9View →

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