High
D1 241 on Worcester Bosch Greenstar CDi Compact

Your boiler has lost the signal from one of its internal temperature sensors, which prevents it from safely controlling your heating and hot water.

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 disconnected

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 240View →

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