BoilerFaultCodesYour boiler has lost communication with its outdoor temperature sensor, meaning it can't tell how hard it needs to work based on the weather.
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 detect a signal from the small sensor located on the exterior wall of your home. The most common reason is that the external wiring has become damaged by weather or garden activity, or the sensor's internal electrical components have failed due to age.
This fault is more frequently reported during autumn and winter when heavy rain or frost can penetrate the sensor housing and corrode the electrical connections.
DIY fix possible
Locate the external sensor box on your outside wallCheck for any visible damage to the box or the wiring leading to itTry resetting the boiler to see if the error clears
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A boiler cover plan would cover faults like F6 — no call-out fees, no surprises.
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