Low
Outside Sensor Fault on Keston Combi C30

Your boiler has lost communication with the sensor that monitors the outdoor temperature, which might make your heating less efficient.

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

Outside Sensor Fault - Contact Installer.

From this model's manual
Verified against the Keston Combi C30 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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Related fault codes

E25View →E26View →

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