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What aggravates me most about the OneLink by First Alert Wi-Fi Smoke + CO Alarm is what it could have been. This is HomeKit's answer to the Nest Protect, and with its killer list of features, I honestly thought it had a good chance to become the smart smoke alarm to beat. It does everything the Protect does like push alerts, voiced warnings, and in-app silencing of false alarms. Plus, the $120 hard-wired version talks to your existing hardwired detectors, letting you smarten up your whole house with one unit and significantly lowering the barrier to entry for whole-home smart smoke detection.
Both the $110 battery-powered version and the $120 hardwired version have sealed batteries -- a backup in the case of the latter -- rated to last 10 years and thus meeting the requirements of certain states with stricter safety standards. First Alert also has a long history of making smoke alarms and safety gear, and that shows in the detector itself -- it consistently responded to smoke and blared its warning faster than the Nest Protect.
At some point, software updates and better HomeKit integration might make this the smoke detector I was hoping for. For now, a bare bones app, horrendously slow push notifications, and meaningless HomeKit functionality make First Alert's alarm a nonstarter as a smart-home product. The connected functionality just isn't good enough to be useful yet. Save yourself the money and get a non-connected $30 to $40 combination sensor, or if you want to get smart with smoke detection, go with the $100 second-gen Nest Protect, or the retrofit $35 Roost Smart Battery.
Before I faced the disappointment of the connected functionality, the OneLink by First Alert Wi-Fi Smoke and CO Alarm made a great first impression on me. Again, the hardware here is solid and responsive. It looks great, and it's easy to set up.
Physically installing the device is almost the same as installing any other battery powered or hard-wired smoke alarm. You'll need enough basic DIY skill to hang it on a wall for the battery version, and you'll need to be comfortable connecting a couple of wires for the hard-wired model.
Both the iOS only app and a set of physical instructions walk you through installing either alarm type, and a separate mounting plate makes the whole process easier, as you can simply focus on hanging that plastic frame, and snap the main body of the smoke alarm into place once the back plate is properly hung where you want it.
Once you twist the alarm onto its mounted backing, the LEDs framing the alarm's central button will flash green, and the alarm will speak a welcome before the lights flash blue, indicating that it's ready to sync to your home's router.
The OneLink Alarm talks to your phone via Bluetooth, and sends you remote notifications over Wi-Fi. Once it's blinking blue, it'll use that Bluetooth connection on your phone to pull the appropriate Wi-Fi info. You'll barely have to do anything other than confirm the name of your network, wait for it to sync, then put in the proper Apple HomeKit ID.
As with any other HomeKit device, you can assign the alarm to a specific home, and then any of Apple's organizational buckets within your home, such as Zones and Rooms. You'll oddly assign the alarm to a specific room twice -- once for HomeKit organization with a name you can spell out yourself, and once from a selected list based on the names the alarm is programmed to say out loud.
When I first set up the alarm, I called the room the "Smoke Test Room" then had to dub it the "Living Room" for the sake of the audible alerts the alarm gives. To be fair, the alarm comes with several different room choice options, so you'll likely find a room name close to your selection, but I still found it slightly confusing to have the same alarm assigned to two different places in a single app.
Once you're up and running, you'll be able to test your alarm from the app and slide the brightness of the nightlight up or down. When the alarm sounds, it blares loudly and it's wildly annoying. I appreciated that. I certainly don't want my smoke detector to be shy if something's wrong. The central LEDs flash red and the alarm rings in a slightly different pattern if it's a smoke or CO emergency, and then a voice notification tells you which emergency it is, and where it is.
Here's where it reads the name you gave it from the listed choices, so my alarm would say, "Evacuate, Evacuate, there's fire in the living room." When testing, you'll see all of this in action, except the voice will clarify that it's testing, and then it'll go on to give you a reading of the parts per million of the carbon monoxide it sensed, before assuring you that the test is now over and you are protected. If the alarm is sounding for real, you'll see a button in the app letting you call 911.
You'll also see the battery percentage level in the app, and it'll let you know when it starts to run low. Since the batteries are sealed, you'll have to replace your detector at that point, which isn't great, but again, this was done to meet stringent safety standards in certain states including California. And it shouldn't happen for 10 years.
In the meantime, you can rest assured that once your alarm smells something wrong, it'll sound its siren loudly and proudly. The OneLink by First Alert Wi-Fi Smoke and CO Alarm uses photoelectric smoke sensors that will supposedly catch both slow- and fast-moving fires while being less prone to nuisance alarms.
In our tests, those sensors proved reliably responsive, consistently picking up on the smoke candles we set off as soon or sooner than the Kidde smoke and CO detector we used for comparison. The second-gen Nest Protect would generally start sounding a few seconds after the Kidde alarm in the same test. As far as hardware is concerned, the OneLink Alarm performed slightly quicker than the Nest Protect.
It also looks fairly similar. That's not a bad thing; we loved the look of the Protect. The all-white First Alert alarm isn't quite as striking, but it's still attractive. And though it's a departure from the usual rounded shape of First Alert alarms, I didn't think the look too derivative of Nest. It's cut from the same cloth, and a small step down, but attractive all the same, and the white finish should blend into your ceiling more as the years go by and you stop thinking about your spiffy new smart smoke alarm.
You can purchase the OneLink by First Alert Wi-Fi Smoke and CO Alarm now on Amazon and the Apple Store. Again, the hardwired model costs $120 (£80, AU$165) and the battery version is $110 (£75, AU$150).
For the price, you'll be getting a fine smoke alarm that makes a great first impression and has smarts and HomeKit compatibility. As it turns out, though, those latter two features don't add much to the experience.
Yes, you can use Siri -- the digital assistant on your iPhone -- to interact with the OneLink by First Alert Smoke + CO Alarm. That's the perk of the alarm working with HomeKit -- the smart-home software built into Apple's mobile operating system. The First Alert Alarm is the first smoke detector compatible with the HomeKit system, and in exchange for following Apple's structural and signal rules for HomeKit, First Alert gets a HomeKit sticker on their box, as well as automatic interoperability with any other HomeKit device.
It's a nice boon for both companies. It makes Apple's HomeKit catalog more diverse, and ups the profile of First Alert's product. As of now, it's not much of a benefit for consumers, since the HomeKit functionality is nearly useless. You absolutely can use Siri to check on the status of your smoke alarm, but doing so doesn't make a whole lot of sense.
Here are the commands currently at your disposal:
Other than the small convenience of being able to alter the brightness of the night light with your voice, I'm not sure how any of these commands are useful. Why would you ever ask your phone if your smoke alarm sensed something? It's the job of the smoke alarm to be proactive. If it senses something, it needs to let you know. If you need to ask if something's up, something went wrong in the communication process.
The Siri functionality on this OneLink Alarm is a feature for the sake of having a feature. And for now, this meaningless add-on is the only perk the OneLink alarm gets from HomeKit. Ideally, if the alarm sounds, it should be able to seamlessly interact with other HomeKit products to flash your Philips Hue bulbs red and unlock your Schlage deadbolt so you can get out of the house more quickly. The triggers for the OneLink Alarm that would allow this aren't ready yet, so you can't do any of this.
Unfortunately, the useless HomeKit integration is just one of the troubles this device has with smarts. If the push notifications and the app were at least reliably responsive, the OneLink alarm could have still been a viable product for HomeKit fans while waiting for the interoperability to develop. They aren't.
Once the alarm sounds, it consistently takes 90 seconds or more for the push notification to come through. Perhaps I'm spoiled a bit by the digital age, but 90 seconds is an eternity. And since this is a safety device, this isn't 90 seconds waiting for an Internet video to load. This is 90 seconds while your home is burning.
And that 90 seconds is the time quoted to me by a customer service specialist at First Alert. After our first couple of smoke candle tests produced no push notifications at all, I reached out because I thought I had a faulty product. As it turns out, we just weren't running long enough tests. Once we blew smoke at the alarm for 90 seconds straight or more, we finally began receiving push alerts and the alarm history in the app would update. Anything less, and the app wouldn't know anything happened.
For perspective, the Insurance Services Organization, or ISO, regulates the distribution of fire stations within a community with a goal of being able to reach all protected homes within 3.2 minutes. It takes First Alert half that time to send a message to your phone.
The sluggishness of the alerts make this OneLink Smoke Alarm a failure as a smart safety device. The Nest Protect's alerts weren't consistently instantaneous either, but they mostly came through within a few seconds. The alerts from the Roost Smart Battery consistently arrived within 1 to 10 seconds.
Not only are the push notifications slow, the app itself also seemingly takes forever to update to alarm status, so forget about using the silencing feature. You'll generally wait 30 to 90 seconds for the app to pick up on the fact that the alarm is sounding.
Then, you'll need to hold down the button to silence the alarm, then have to wait for another slow sync up before the alarm finally shuts down. Sometimes, the app will decide there's too much smoke to shut off, and will keep sounding despite your request for silence. I understand the reasoning for that override, but it proved quite annoying in practice.
All told, if you want to use the app to silence your alarm, expect to spend two to three minutes listening to it blare first, by which point you could have easily toweled away the smoke or gotten fed up enough to smash the thing into pieces with a hammer.
The app will catalog the history of your alarms -- a feature that didn't work at all on the second-gen Protect -- but again, only if the alarm is sounding for at least 90 seconds.
First Alert told me that the reason for the delay is the alarm prioritizes sending a signal to the other alarms in your house first. That seems a reasonable order of operations, as it's the people in the home whose lives are potentially in danger, and we indeed found that a second OneLink by First Alert Alarm would start sounding almost immediately after the first. The second alarm even spoke the correct room. So if I blew smoke at my connected "Living Room" alarm, the alarm I had set up for the "Kitchen" would still tell me that smoke was detected in the living room.
The hard-wired version of First Alert's smart alarm is also supposed to communicate with certain hard-wired dumb alarms. I loved the idea of this feature. Ideally, when my smart First Alert Alarm sounded, all other interconnected alarms would sound as well. And more importantly, when my dumb alarms sounded, I wanted my First Alert alarm to know, start it's own alarm, and send me a push notification. Unfortunately, as was the case with the rest of this alarm's smart features, the reality fell well short of the ideal.
We hard-wired a First Alert 9120 alarm next to the OneLink by First Alert Wi-Fi Smoke and CO Alarm, with enough distance apart that we could direct smoke at one or the other without blowing it on both. Oddly, every time the smart OneLink Alarm sounded, the 9120 alarm would whir into action shortly after. This happened reliably, and always within a matter of seconds.
Going the other way -- sending the signal from the dumb alarm to the smart one -- wasn't nearly as reliable. It tended to take anywhere from 90 seconds to two full minutes of either blowing smoke at the dumb alarm or holding down the test button before the OneLink Wi-Fi Alarm would do anything. At that point, it would ring a couple of times, begin its vocal warning, then stop part way through its voice message, despite the fact that the dumb alarm was still ringing.
To be fair, we didn't expect the OneLink Alarm to know the correct room for the dumb alarm, but the fact that it stops sounding all together is problematic, and we never once got a push alert from the OneLink Alarm when prompting it via its dumb counterpart. The whole appeal of the feature -- adding smarts throughout your home with a single connected unit -- doesn't work.
Obviously, some signal is making it between the two alarms, but the OneLink Alarm doesn't know what to do with the signal it gets from a nonconnected unit. And this half-baked interconnectedness certainly isn't polished enough to excuse the extreme delays in push notifications.
Aside from the major gaps in functionality, the app itself is also shallow and lacks customization. You can't see or control any other HomeKit devices with it, as you can with a few HomeKit apps, and you can't even access any in depth options for the OneLink Alarm, such as scheduling when the nightlight should turn on. The app doesn't get the basics right since push notifications and silencing is so slow, and it doesn't have any advanced features. It's not completely broken, but that's as much as I can say about it.
Smarts on your smoke detector can help you in two ways. The connected functionality can increase your safety by letting you know something's wrong when you're away, allowing you to take action. It can also add convenience to your life by letting you silence an annoying false alarm more quickly, without having to wave a towel around or grab a broomstick to hit the silence button. Because of the poor response time of the app, the OneLink by First Alert Wi-Fi Smoke and CO Alarm doesn't work in either sense.
The $100 second Gen Nest Protect does both well enough. I recommend that if you want a wholesale replacement, or the $35 Roost Smart Battery makes for an appealing retrofit option. It packs smarts into a familiar 9V battery and was quite responsive in our tests.
The nonconnected aspects of the OneLink by First Alert Wi-Fi Smoke and CO Alarm work fine, and that alone makes it worth more than simple $20 smoke detectors. But combination smoke and CO alarms with voiced warnings can be had for $40 to $50, and OneLink's $110 to $120 HomeKit alarm doesn't add any useful functionality on top of those.