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Test/replace smoke detector batteries
Trigger
Every 6 months (time-change reminder)
Who does it
DIY
Est. time
10 min per detector
Est. cost
$5-10
Difficulty
●○○○○
Step by step
Press the test button on each detector and listen for the alarm tone.
Open the battery compartment and swap in a fresh battery (9V or AA depending on model).
Reinstall and press test again to confirm it's working.
Vacuum dust from the vents on the detector housing.
Replace the entire unit if it's over 10 years old, regardless of battery.
Video guide
How to Install a Hard Wired Smoke Detector - Family Handyman
Watch this guide
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