Medium Warning
51132 on Worcester Bosch Greenstar CDi Compact

Your boiler has lost communication with the temperature sensor that monitors your hot water cylinder, meaning it may not know when to stop heating 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

Temperature sensor type PTC 1000 used as cylinder temperature sensor (T2).

What causes this fault?

This fault occurs when the electrical connection between the boiler's control board and the hot water cylinder’s temperature sensor is broken or sending an incorrect signal. The most common reason is a failed internal component within the sensor itself or a wire that has become loose or damaged over time.

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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