First Alert Onelink Safe & Sound Smoke + Carbon Monoxide Alarm REVIEW

7 min readJul 23, 2018

When you think about your family at home, you think about safety. You invest in the best door locks possible, you make sure the windows close securely, and you always make sure the battery in the smoke detector is still good. When we bought our house a few years back, there was one standard budget smoke detector in our hallway. It was functional, but it was only designed to warn us if there was smoke present. So, we upgraded to a smart device that also detected carbon monoxide. The Onelink WiFi Smoke and Carbon Monoxide Alarm by First Alert was an excellent choice for our household as it connected to our smartphones to send us notifications wherever we are and it was also HomeKit compatible. Over time, our smart home has evolved to not only include HomeKit devices, but also those compatible with Amazon Alexa. I actually love devices that have Alexa integrated like the new Onelink Safe & Sound Smart Smoke + Carbon Monoxide Alarm also by First Alert. Needless to say, when I learned about this product, I upgraded our older WiFi alarm from Onelink and installed this one.


The Onelink Safe & Sound Smart Smoke + Carbon Monoxide Alarm is an Apple HomeKit enabled device that is also a speaker with Amazon Alexa integrated. This is the first-ever smart smoke and carbon monoxide alarm with a built-in Alexa Voice Services. In addition to having a strong safety alarm integrated, the Safe & Sound can also play music, audiobooks, read you news, and even control smart home devices. Because the alarm is installed on the ceiling, the speaker will fill any room with 360-degree audio. The alarm has an advanced microphone with noise-canceling technology which allows the Safe & Sound to hear you from any direction. The alarm is powered by First Alert’s technology for smoke and carbon monoxide detection and will warn you of any danger in your home with an 85-decibel alarm and through your smartphone. The Safe & Sound currently works with Apple HomeKit, the Apple Home App, and will be compatible with AirPlay 2 later in 2018.


  • Smart Smoke and Carbon Monoxide Alarm for Home Protection
  • Premium Home Speaker for Audio and Entertainment
  • Works with Apple HomeKit
  • Embedded Alexa Voice Services for Convenience and Control
  • Hardwired Alarm with Easy Setup and Installation
  • Mobile Connectivity Through the Onelink Home App
  • Airplay 2 Compatibility Available Later this Year


The Onelink Safe & Sound came in a beautiful Onelink branded box. Normally, I don’t express beauty when it comes to product packaging, but for me, the branding and box design was eye-catching and memorable. There is a clear image of the device on the front with the Apple HomeKit and Amazon Alexa logos on the front. The box also makes it very clear that the device is a 3-in-1 product (smoke & carbon monoxide alarm, home speaker, and Alexa-enabled device). Aside from that, the packaging is pretty straightforward. It has an ample amount of information included, but not so much that it distracts any potential buyers from what the device is all about.

When you first open the box, you will find the Onelink Safe & Sound Alarm itself. It’s set inside a plastic mold that holds the alarm securely in place. When you pull the alarm out you’ll find the rest of the contents: a user manual, a “Get Started with Alexa” card, various wiring harnesses, the mounting plate, and screws. It’s important to note here that this device must be hardwired into your home’s electrical system. If you don’t have a place to tie in, you may want to enlist a professional electrician to give you a wiring drop and box for this alarm.

This is actually a step that we had to take when installing the Onelink WiFi Smoke and Carbon Monoxide Alarm and since we already had the wiring drop from that, installation of the Safe & Sound Alarm was a pretty easy job. First Alert designed the Safe & Sound to connect to an electrical system using a plug-based wiring harness. This means you simply snap a plug into place and your new alarm will have power. The only steps we really had to take with installation was to swap out the mounting plate, connect the new alarm to the pre-installed plug, and then snap the alarm into the mounting plate. You’ll know that power is connected properly when the LED nightlight will start blinking indicating that the alarm is ready for set-up.

At this point, I turned to the mobile app to connect the alarm to HomeKit and Alexa. The app will display a few highlights (microphone button, interrupt button, and nightlight button) and then take you to a screen where you select the device you want to connect. The app will direct you to set-up the product by choosing the room you want it in and what type of alarm announcement you want (i.e. “Smoke is detected in the Living Room.”). I chose Hallway for both options because that is where our Safe & Sound is located. The app will also prompt you to enter the HomeKit code to connect it to your home. In my case, the alarm was connected, but with “issues” and I got what looks like an error screen. Don’t be concerned if you see this screen. It only means that you still have a step to complete to connect the alarm to Amazon and the Alexa services.

Once set-up is complete and you are connected to all your applicable services, the alarm operates normally without any interaction from you. There is a test/silence button on one of the sides that you can press to test the alarm or silence it depending on your need at the time. One of the additional features to this device that makes it a substantial upgrade to the previous model I had installed is the Bluetooth speaker that’s integrated. It’s a little bit of an odd pairing, but when you think about how smoke detectors are usually centrally located in a home, it makes sense. The only really strange thing about this integration is that you have to connect to the speaker as a standard Bluetooth speaker (through your Bluetooth menu) and then you can control it from the Onelink app. This is really the only thing I would change about the Onelink Safe & Sound — how the speaker is controlled/paired. I would love it to be more self-contained and since the device is already connected through HomeKit and WiFi. It’s rumored that Safe & Sound will eventually support AirPlay 2 when it’s available so that will be a much better connectivity option than Bluetooth as that is sometimes spotty when streaming.

As far as the connection with Siri and Alexa goes, the speaker has a really great microphone and can actually hear me across the house. This was a blessing and a curse at the same time because I would try to talk to an Echo in our Living Room and hear the Safe & Sound respond with “Ok” instead of the intended Alexa device. This was more of an annoyance than a problem. But, one thing I did like was to be able to tell Alexa to play music and have it streaming directly from the alarm’s speaker. The speaker quality is average and it’s really more about convenience than a premium quality speaker. It sounds good and it works well but it’s not really meant for the audiophile’s keen ear.


The Onelink Safe & Sound alarm is a very nice addition to any smart home. It’s an easy installation process especially if you already have an electrical tie-in. The speaker is a really interesting option for this device and in my opinion, makes it complete. I love that it has such an easy set-up process and that it’s one of those devices that you can set-up and leave it to do its job. I can recommend this alarm to anyone who wants to step up their smoke and carbon monoxide detector equipment.

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Originally published at on July 23, 2018.




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