BoilerFaultCodesTechnical description
Outside sensor fault
What causes this fault?
This fault occurs when the boiler can no longer communicate with the small sensor installed on the exterior wall of your home. It is physically caused by either a failure of the sensor’s internal components or, more commonly, damage to the thin electrical wiring that connects the sensor to the boiler. Without this signal, the boiler cannot adjust its heat output based on the weather outside.
This fault is more common following periods of heavy rain or freezing temperatures, which can cause moisture ingress or wire degradation in the outdoor sensor housing.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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