BoilerFaultCodesTechnical description
Outside temperature with weather compensator – Vaillant controller only
What causes this fault?
This fault occurs when the boiler loses communication with the sensor located on the outside of your home, which tells the system how hard it needs to work based on the weather. The most common reasons are a loose connection in the wiring, a faulty sensor unit, or corrosion caused by exposure to the elements over several years.
This issue is often identified during the first cold snap of autumn when the boiler attempts to use the outdoor temperature data to adjust the heating for the first time in months.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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