High
D1 240 on Worcester Bosch Greenstar CDi Compact

Your boiler has stopped working because it is unable to accurately measure the temperature of the water returning from your radiators due to a faulty sensor signal.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Return sensor short circuit Wet sensor.

Engineer required

This is a high severity fault. Stop using the boiler and call 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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