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user_hud094 That is a great question! It may be the sensor not being sit tight next to the other part of the sensor. I have a room at the front of my house that gets lots of air when doors open or shut and it can cause the sensor to trigger as the window moves just a bit. I had to take the sensor off and reset it to be better aligned to the top. See if that helps they are sensitive due to the nature of the devices of course but when aligned correctly it should not be an issue.