What does the Worcester Bosch Autofrostat Function fault code mean?

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.

How much does it cost to fix Worcester Bosch error code Autofrostat Function?

Cost varies. Contact a Gas Safe registered engineer for a quote.

Worcester Bosch Autofrostat Function Fault Code: What It Means & How to Fix It

What the manual says

Manufacturer manual

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

Shared across the 28Si range

This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.

Engineer required

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

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All 11 fault codes on the 28Si

Seeing a different code? Every code this model can display, in one place.

2 lights flashing fast CH light On F1 F2 FAIL POINT K Fan runs Fast flash Lock-out Pump runs Slow flash

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.

What the manual says

Engineer required

Avoid the next call-out bill

All 11 fault codes on the 28Si

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