Medium
375 E4 on Worcester Bosch Greenstar CDi Compact

Your boiler is having trouble detecting the temperature of the incoming cold water supply due to a faulty electrical connection or sensor.

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

Preheat sensor on DHW inlet Short Circuit

Engineer required

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

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