High
810 on Worcester Bosch Greenstar 8000 Style

Your boiler is currently unable to provide hot water, meaning you will likely have cold taps and a cold shower until the fault is corrected.

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

Hot water remains cold

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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