Medium Lockout
Fault 51 132 on Worcester Bosch Greenstar CDi Compact

Your boiler has lost communication with the temperature sensor that monitors your hot water cylinder, meaning it cannot accurately 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

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

What causes this fault?

This fault occurs when the boiler's control board can no longer detect a signal from the sensor attached to your hot water tank. It is usually caused by the sensor itself failing internally or the electrical wiring becoming loose or damaged over time, preventing the boiler from knowing how hot your water is.

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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