Low
Boiler temperature below 8°C on Worcester Bosch Greenstar 30si

Your boiler has detected that the water inside it is very cold and has automatically activated its internal frost protection system to prevent the pipes from freezing.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Run autofroststat function

DIY fix possible

Ensure your heating controls are set to a temperature that keeps the boiler active during very cold weatherKeep your heating on a low constant setting if temperatures are near freezingDo not switch off the power supply to the boiler

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