Medium
D1 240 on Worcester Bosch Greenstar 12i System

Your boiler has detected a faulty reading from a temperature sensor and has temporarily paused its operation to prevent any potential issues.

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

Return sensor error - Sensor wet or damaged (the boiler will block for 300 seconds before this condition).

Engineer required

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

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Related fault codes

D1 241View →

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