06-23-2011, 01:04 AM
they should be replaced every 5 years. The detector sensor has a limited life. Mine came with a lithium battery, and in about 5 years when the battery dies, toss the detector and buy a new one. DON'T replace the battery. My old one, from the same manufacturer, had the battery go out about a year ago. I replaced the battery and within a few months, it was giving off a lot of false positives, even with the windows open in the middle of the summer. The local gas company told me that it is a common thing. This was also verified by a buddy who works for the gas company running 2 of their power plants, but interned with the natural gas delivery dept for 6 months.