BoilerFaultCodesYour boiler has lost connection with the sensor that measures 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: 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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A boiler cover plan would cover faults like F6 — no call-out fees, no surprises.
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