How to Install Batteries in a Home Smoke Detector

According to the U.S. Fire Administration, both standard smoke detectors and hardwired smoke detectors that use batteries as a backup will need to have their batteries replaced at least once annually. If you have never changed a smoke detector battery, don't worry. The task is easy to accomplish and will take you no more than a few minutes.

Things You'll Need

Stepladder

1 9-volt battery

Instructions

- 1
  Position your stepladder under the smoke detector and climb to the top.
- 2
  Reach up and grab the sides of your smoke detector with both hands. Twist the casing counterclockwise and the detector will detach from the base, which is screwed into the ceiling.
- 3
  Pull the tab that connects the detector to the base. This releases the detector so you can bring it down toward you.
- 4
  Use a fingernail to pry open the battery compartment and pry out the battery. Detach the battery from the terminal.
- 5
  Attach a new 9-volt battery to the terminal and tuck it back into the battery compartment. Close the tab of the battery compartment.
- 6
  Reach up and clip the connector back onto the smoke detector. There's only one way that it can go in.
- 7
  Align the tabs on the smoke detector and base and twist clockwise to reattach it to the base.
- 8
  Test the smoke alarm by pressing the button on the detector. This will ensure the new battery is operating properly.

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Smoke Detectors