Low
1 nn on Keston C40

Your boiler is currently performing a standard pre-ignition safety check by running its internal fan to clear the system, which is a normal part of the start-up sequence.

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

Boiler is running fan prior to attempting ignition

From this model's manual
Verified against the Keston C40 installation & service manual, page 31.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Wait 5 minutes to see if the boiler completes the start-up sequence automaticallyCheck if the display changes to a normal operating temperature after the fan stopsIf the code persists for more than 15 minutes, perform a soft reset of the boiler

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