Low
Fan runs on Worcester Bosch 28 i SI

Your boiler is operating normally, as the fan is running to move air while the water temperature is at a safe, functional level.

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.

What the manual says

Manufacturer manual

Primary temperature 75°C

From this model's manual
Verified against the Worcester Bosch Greenstar 25si installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

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

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