High
E9 on Worcester Bosch Worcester 25/30 HE

Your boiler has switched itself off because it has detected that the internal water or exhaust gases have reached a dangerously high temperature.

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 (primary heat exchanger) or flue gas temperature limiter has operated

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

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