High
i10 on Worcester Bosch Greenstar Heatslave II

Your boiler is temporarily shutting down because it has detected that the internal water temperature has become dangerously high.

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

Maximal temperature - This is the current temperature from the “maximal safety sensor” displayed in real time (rounded to 0.5°C units). The sensor is mounted on the top of the primary heat exchanger.

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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