BoilerFaultCodesYour boiler has lost communication with the sensor that monitors the outdoor temperature, meaning it might not heat your home as efficiently as usual.
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 outside of your property. The most common reasons are physical damage to the external unit from weather exposure or the electrical wiring becoming loose or corroded over time. Because the boiler doesn't know how cold it is outside, it can't automatically adjust its temperature to provide the most efficient heating.
This fault is often noticed during the first cold snaps of autumn or after heavy winter storms when wind or ice may have disturbed the external wiring.
DIY fix possible
Check the outdoor sensor for any obvious physical damage or loose wiresEnsure the sensor is not covered by snow, debris, or overgrown plantsReset the boiler to see if the fault clears
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