BoilerFaultCodesYour boiler has lost communication with the sensor that monitors the temperature outside your home, which may affect how efficiently it heats your radiators.
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: Outdoor sensor error
What causes this fault?
This fault occurs when the boiler loses signal from the small sensor mounted on an external wall of your property. The most common reason is a break or loose connection in the wiring between the boiler and the sensor, though it can also be caused by the sensor itself failing due to water ingress or age.
DIY fix possible
Locate your boiler's reset button or dial.Press or turn to 'Reset' and hold for five seconds, then release.Wait for the boiler to restart to see if the error was a temporary glitch.
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A boiler cover plan would cover faults like E10 — no call-out fees, no surprises.
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