High
224 V on Worcester Bosch 30i Junior

Your boiler has switched itself off because it has detected an unsafe rise in temperature, usually caused by low water pressure or a blockage in the system.

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 has tripped – top-up water until the reset pressure is reached

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

E9View →

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