BoilerFaultCodesTechnical description
Outside sensor failure
What causes this fault?
This fault occurs when the boiler can no longer detect a signal from the small sensor located on the exterior of your home. The most common reason is that the sensor itself has developed a fault due to exposure to the elements, or the thin electrical wiring connecting it to the boiler has become damaged or loose. Because the boiler doesn't know how cold it is outside, it can't automatically adjust its settings to save you money on your heating bills.
This fault often comes to light during the first cold snap of autumn when the boiler attempts to communicate with the sensor to adjust for dropping temperatures.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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