Indoor Sensor
@lucienve makes a great point that you could be seeing an indoor sensor. If it has a black ring around the icon, it’s an indoor sensor.
Low-Confidence Sensor
Otherwise, it’s possible that it’s a low-confidence sensor with a laser counter that has a dead fan. If it’s slightly transparent compared to nearby sensors, you can be almost certain that this is the case. We have an algorithm that attempts to track these down, but it doesn’t catch all of them. If you can share details about the sensor (Sensor Index or Name), we might be able to do something about it.