How often should smoke detectors batteries be replaced

You should replace your smoke detectors at least every 10 years

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It’s important to test and replace faulty smoke detectors regularly for the health and safety of you and your family. In addition, it’s a requirement in most states for residences and rental properties to have working smoke detectors. 

Find out how long the typical smoke detector lasts and how you can test its functionality so you can have peace of mind

How Long Smoke Detectors Last

The National Fire Protection Association recommends replacing a smoke detector when it is 10 years old. Over time, dust gathers inside smoke detectors, wearing down the sensors. Older smoke detectors are less sensitive, which means when there is a fire, you may not have enough time to escape by the time the alarm goes off. They are also more susceptible to electrical corrosion.

Even if a smoke detector hasn’t reached the 10-year mark, replace it if it chirps even after you’ve replaced the battery or if the alarm doesn’t sound when you perform the recommended monthly test. Experts recommend replacing all connected smoke alarms at the same time, even if some are working.

How to Maintain Your Smoke Alarms to Keep Them in Working Order

The U.S. Fire Administration (USFA) encourages homeowners to replace smoke detector batteries (or the backup batteries if you have hardwired smoke alarms) at least once a year and test the alarms monthly to ensure none need to be replaced.

Signs It’s Time to Replace Your Smoke Detector

Here’s how you know if a smoke detector is going bad and when you should take action.

You Hear a Chirping Sound

A smoke alarm that needs attention will chirp for a long time, sometimes indefinitely, if it is hardwired to your electricity. But you’ll want to make sure you take action ASAP once you hear that sound because it means the batteries in the smoke detector are going bad and need to be replaced.

It Is More Than 10 Years Old

As mentioned above, age can be a big indicator that it’s time to replace a smoke detector. It’s pretty simple to check the age of your smoke detector: Just climb up on a ladder and take a look at the back of the alarm up-close. There will be a manufactured date that tells you when the alarm was made. If that date was 10 years ago or more, it’s definitely time to replace it. 

Do this same check on all the smoke alarms in your house, as many homes have had all their smoke detectors installed around the same time. Note: If your smoke detector is on a high ceiling, you may need to call someone for the job.

Cost to Replace Hardwired Smoke Alarms

How often should smoke detectors batteries be replaced

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You can replace hardwired detectors yourself, if you can reach them and if you have skills sufficient enough to replace a light fixture. (Be sure to turn off electricity at the breaker box first, though.) Otherwise, you can hire an electrician or an alarm service company to do the job.

The cost to replace a smoke detector can vary widely, depending on where you live, the type and number of units you need to replace, where they are, and the condition of the wires. A smoke alarm itself can cost as little as $10 per unit for a basic model or as much as $50 per unit for a wireless or hardwired smoke alarm with a built-in carbon monoxide detector. 

A local home security company can do the installation for you if you prefer this peace of mind. These service providers typically charge $35 to $40 per detector plus a $50 service charge.

8 Important Fire Safety Tips to Protect Your Family and Home

These fire safety tips from the NFPA will help you and your family make a plan and stay safe.

  • Install smoke alarms inside and outside each bedroom and sleeping area. Install alarms on every level of the home, including the basement. (Large homes may need extra smoke alarms.) 

  • Interconnected smoke alarms—whether hardwired or wireless—are best because when one is activated, they all sound. 

  • Test all smoke alarms at least once a month. Simply press the test button to be sure the alarm works.

  • There are two types of smoke detectors. Ionization smoke alarms are quicker to warn of flaming fires, whereas photoelectric alarms are quicker to warn of smoldering fires. It’s best to use some of both types throughout your home. 

  • A smoke alarm should be on the ceiling or high on a wall. Install wall-mounted alarms no more than 12 inches from the ceiling to the top of the alarm.

  • Don't install smoke alarms near windows, doors, or ducts where drafts might interfere with their operation. To reduce false alarms, keep alarms at least 10 feet from a stove. 

  • Make sure everyone in your home knows how to respond if they hear a smoke alarm.

  • Follow the manufacturer’s instructions for cleaning smoke detectors.

Frequently Asked Questions

You should change the batteries in your smoke detectors at least once per year. Mark it on your calendar or make it a holiday or birthday tradition so that you always remember it. You should also be testing your smoke alarms monthly to ensure they’re working properly. 

There are a few reasons why your smoke detector may be beeping. For one, make sure the batteries you use are fresh. If they are, look at the manufacturing date on the smoke alarm. If it’s more than 10 years old, this could be the detector's way of telling you that you need to replace it. You may have also tripped one of the test buttons or another setting so consult your manual for more info.

Hardwired smoke alarms connect to the power in your home, and they also have backup power in case of an outage. They can operate in tandem with each other, sounding the alarm in every room when smoke is detected in one part of the home. Battery-operated smoke detectors, true to their name, are run by battery power. You’ll need to change the batteries yearly and they typically operate solo.

How long do 9v batteries last in smoke detectors?

9-Volt Battery The 9-volt battery smoke detectors are the standard and most common model. These detectors require you to change out your batteries once every year or so. After they hit the 8-year mark you should consider replacing it. A 9-volt battery detector can live up to 10 years if you take care of it.

What happens if you don't change the batteries in a smoke detector?

A smoke alarm will eventually stop chirping if you do nothing. Once the battery has run out completely, the device will switch to residual power. Eventually, this will also drain and the device won't have enough power to beep and let you know it's out of power. You should change the battery before this happens.

Do smoke alarm batteries last 10 years?

Ten-year sealed battery smoke alarms are powered by sealed lithium batteries that have a life span of ten years.

Why is my smoke detector flashing a red light?

The Batteries are Low: Usually accompanied by a loud beep, a blinking red light could mean the batteries in the unit are low. Consider adding fresh batteries and running a test to make sure it's working. It Needs to Be Replaced: Smoke detectors don't last forever.