High
E9 on Worcester Bosch 35 RSF

Your boiler has shut down because a sensor has detected that the water inside is getting too hot, or there is a problem with the circulation or pressure preventing safe cooling.

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 limiter in central heating (CH) flow has tripped the system pressure or safety temperature limiter needs checking

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

E2View →B1View →

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