High
Group 2, 7 flashes on Worcester Bosch Greenstar CDi Compact

Your boiler has detected that it is running much too hot and has automatically shut down to prevent damage or dangerous 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 temperature too high. The main heat exchanger has overheated. Maximum temperature 105°C.

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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