We have smoke detectors in new construction, so the smoke detectors are wired in to the house's electricity with a back up battery. Quite frequently one of the smoke detectors located in my son's room beeps at a rate of about once every 30 seconds. It doesn't do it all the time, mostly in the late afternoon or evening. My only theory is that his room tends to get hotter than the rest of the house, that maybe the detector is sensing the temperature. Sometimes if we crank up the AC it will stop beeping after a while. However, I am not convinced about my theory, because it doesn't always work. Plus, if it is beeping because of the heat (about 76 degrees), it seems too sensitive. I welcome any advise.