Low
Autofroststat mode on Worcester Bosch Greenstar 15sbi

Your boiler has detected very cold temperatures nearby and has temporarily turned itself on to prevent your 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

Boiler is running in frost protection mode because it is in a very cold environment.

DIY fix possible

Ensure your boiler is left switched on and connected to the power supplyCheck that your external condensate pipe is insulated to prevent freezingEnsure the room where the boiler is located is kept above freezing point

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