BoilerFaultCodesYour boiler has lost connection with its external temperature sensor, which means it cannot adjust its settings based on the weather outside.
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 not detected
What causes this fault?
This fault occurs when the boiler's main control board loses the electrical signal from the sensor located on the outside of your home. The most common reason is that the sensor itself has failed due to age or moisture, though it can also be caused by a broken or corroded wire connecting the sensor to the boiler.
This fault is often first noticed in autumn or winter when the heating is turned on and the boiler fails to adjust its temperature to match the colder outdoor conditions.
DIY fix possible
Check if the outdoor sensor has been physically damaged or knockedInspect the sensor for any loose wires if it is easily accessiblePress the 'Reset' button on the boiler control panel to see if the connection re-establishes
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