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Your boiler is struggling to detect the temperature of your hot water cylinder, meaning it may not heat your water correctly until this sensor is checked or replaced.

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 temperature sensor not detected.

Engineer required

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

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