Low
Autofrostat Function on Worcester Bosch 28 RSF

Your boiler has detected that the internal temperature is very low and has automatically activated its built-in frost protection mode to prevent the system 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

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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