BoilerFaultCodesTechnical description
Outside Sensor Fault
What causes this fault?
This fault occurs when the boiler is unable to receive a clear electrical signal from the sensor mounted on your external wall. The most common reason is that moisture has entered the sensor casing, causing corrosion, or the thin wiring connecting it to the boiler has become damaged or loose and cannot complete the circuit.
This fault is often triggered during periods of heavy rain or high humidity, as moisture is more likely to breach the sensor's external weatherproofing.
DIY fix possible
Locate the reset button on the front of the boiler display.Press and hold the reset button for 2 seconds.If the code persists, check that the external sensor on your outside wall hasn't been blocked or damaged.
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