Functioning smoke detectors are extremely important in maintaining the safety of your home. Smoke detectors need to be replaced every 10 years, and smoke detector batteries should be replaced every 6 months.You may need to replace your smoke detector The process takes just a few minutes and only requires a screwdriver and some electric tape.f a unit is making a chirping sound, the batteries need replacing. Replace the batteries in the units you’ve identified as malfunctioning and re-test them. Remember that smoke detectors should be replaced every 10 years, even if replacing the batteries fixes them temporarily.