High
E9 277 on Worcester Bosch 35 RSF

Your boiler has shut down because its internal safety system has detected that the water inside has become dangerously hot.

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

The safety temperature sensor has measured temperature in excess of 95°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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Related fault codes

E9 224View →B1View →

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