High
342 on Worcester Bosch Greenstar 8000 Style

Your boiler is switching itself off because the water inside is heating up much faster than it safely should during hot water production.

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

Temperature rise during hot water mode too rapid

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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