How to change a smoke alarm battery
Working smoke alarms reduce the risk of fire in your home and help protect the lives of the whole household. Make sure your smoke alarms are working properly by testing each one and replacing their batteries at least once a year. It’s easy to do – we'll show you how with this simple guide.
Safety tip: Always wear the appropriate safety equipment (safety glasses, gloves, ear muffs and a mask, for example) and always follow the instructions for the product or equipment.
Identify what type of smoke alarm you have
There are different types of smoke alarms. Some use lithium batteries and last for up to 10 years, but the whole unit needs to be replaced once it expires. Other detectors have interchangeable batteries.
To identify which smoke alarm you have, look at the little light on it. A steady green LED light indicates that your alarm is using AC power (it’s wired to the mains electricity in the home). Battery-operated alarms will have a quick flash every 30–45 seconds.
Remove the smoke alarm from the bracket
If you have a battery-operated smoke alarm, remove the smoke detector from its mounting on the ceiling. The method you use will vary depending on which type of smoke detector you have. Most models can be removed by twisting, sliding or clicking a click-into-place bracket. Some models require you to remove a section that covers up the batteries as opposed to removing the entire detector.
Replace the old battery
Once you’ve safely removed your smoke detector or battery cover, remove and discard the old batteries. Install the new batteries correctly, lining up the negative and positive connections as labelled on your smoke detector.
Secure the smoke alarm
Close the battery cover and secure the smoke alarm back onto its mounting bracket.
Do a test run
Once you've reattached the smoke detector, do a test run to make sure the batteries are working properly. Locate the test button and press it down for a few seconds to engage the test. If your batteries are working properly, your smoke alarm will let out a sound. If there is no sound, you’ll need to try different batteries or look at resetting the entire alarm. You can do this by pressing down the reset button for 15-20 seconds. Repeat these steps until you hear the alarm make a sound when testing it.
Looking to install a smoke alarm?
Check out our handy step-by-step guide.
Asbestos, lead-based paints and copper chromium arsenic (CCA) treated timber are health hazards you need to look out for when renovating older homes. These substances can easily be disturbed when renovating and exposure to them can cause a range of life-threatening diseases and conditions including cancer. For information on the dangers of asbestos, lead-based paint and CCA treated timber and tips for dealing with these materials contact your local council's Environmental Health Officer or visit our Health & Safety page.
When following our advice in our D.I.Y. videos, make sure you use all equipment, including PPE, safely by following the manufacturer’s instructions. Check that the equipment is suitable for the task and that PPE fits properly. If you are unsure, hire an expert to do the job or talk to a Bunnings Team Member.
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