High
815 on Worcester Bosch Greenstar 8000 Life

Your boiler is struggling to accurately read the temperature of the water circulating through your heating system, so it has stopped working as a safety precaution to prevent overheating.

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

Low loss header temp. sensor faulty

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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