High
380 on Worcester Bosch Greenstar Heatslave II

Your solar water heating system has detected that the water inside your hot water tank is dangerously hot.

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

Solar tank overheat: DCW in 80°C or more (for 2 seconds or more). fault code displayed within service menu (i1).

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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