1. Keep the cover/body of the detector covered and gently open the cover or unclip it from the base.
2. There are three pieces inside: the sensing chamber, a horn, and the battery
3. Replace the battery with a new one. Make sure it’s secure, and that the ends are matched and placed correctly
4. Close the cover or re-attach the body, making sure it’s locked into place.
5. Test the detector by pressing the ‘test’ button. The detector should make a noise to confirm it’s working.