Low
Autofrostat Function on Worcester Bosch Greenstar 25Si

Your boiler has automatically turned on its frost protection mode because the internal temperature has dropped close to freezing point.

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

No demand and primary temperature below 8°C. Monitor central heating sensor: Below 5°C / 5°C to 9°C / Above 9°C

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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