BoilerFaultCodesYour boiler has lost its connection to the sensor that monitors the temperature outside, which helps it run more efficiently.
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 can no longer communicate with the small sensor mounted on the outside wall of your home. It is usually caused by a break in the thin communication wires, water getting into the sensor housing, or the sensor itself failing due to age. Without this signal, the boiler becomes 'blind' to the temperature outside and cannot adjust its efficiency automatically.
This fault is frequently discovered during autumn or winter when heavy rain or frost damages the external wiring or when the boiler tries to use the sensor more actively to manage heating demands.
DIY fix possible
Check if the boiler has been accidentally switched to a weather-dependent mode without a sensor installedInspect the outdoor sensor for any obvious physical damage or loose wires if you have onePress the 'Reset' button on the boiler control panel once to see if the fault clears
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