High
220 on Worcester Bosch Greenstar CDi Compact

Your boiler has detected a faulty sensor reading, which has automatically shut the system down to prevent overheating.

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

Safety sensor short circuit. Maximum temperature sensor on the main heat exchanger has failed.

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

221View →224View →

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