This is Part 2 of a six-part series to help you better understand your home’s electrical system components. You can see the other parts here.
Your home may have electrically operated smoke detectors. If so, when one detects smoke and sounds the alarm, all detectors in the house will ring with it. They are electric with a battery back-up. The batteries should be changed annually or as directed by the manufacturer.
The detectors have an indicator light and a button that is used to test the system. When the button is pushed on a detector, all the detectors in the house should ring. It is recommended that this test be done monthly to insure the system will work if needed. The expected useful life of a smoke detector is ten years.