High
E9 220 on Worcester Bosch 26 CDi Xtra

Your boiler has shut down because it has detected an unsafe level of overheating or a serious fault with its primary temperature sensor.

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 contacts for the safety temperature sensor have shorted or the safety temperature sensor has detected a temperature higher than 130°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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