For a few years now I have been searching for an ideal replacement of my 6 Nest Protect smoke alarms. Based on my research it appears that the recently announced SC5 from First Alert is the intended replacement (by Google) for the Nest Protect. A youtube video by First Alert also showed that you can mix and match Nest Protect with SC5 enabling the replacement of the detectors as they expire.
First Alert SC5 Hardwire Smart Smoke and Carbon Monoxide Alarm
SKU: FSMCO600NVACCL1
Since I am mostly happy with Nest Protectās features, the SC5 seems to be an ideal replacement given they are supposedly equivalent in functionalityā¦ BUTā¦ do they integrate into Home Assistant or will they have the same support issues the Nest Protects have?
So am interested in the same question! Would love to start bringing (or replacing) the few cloud devices I have to local operation only.
Was very disappointed but not shocked that Google decided to abandon the platform. Fortunately did not use HA for anything related other than the Thermostats (which is another topic for discussion).
I just replaced one of my Nest smokes with the SC5 - and it seemed to work fine. It came with an adapter so no rewiring and it mounted right onto the existing bracket, had to download yet another app to install but it all went smoothly - it did keep trying to insist I use chrome as the browser on my android phone but eventually by switching to ādesktopā it seemed to go through. I think itās now part of the Nest wireless interconnect but have not tested yet.
I just bought 9 First Alert SC5 devices to replace 9 of my 13 Nest protects that all expired at the same timeā¦
I can confirm: They do NOT work with the existing Nest Protect HACS integration and I (so far) have not found any other integration for First Alert for Home Assistant.
I am also disapointed that the First Alert app dosnāt support iOS critical notifications. Meaning you wont get alerted even if your device is in DND mode. You need to link the devices to your google account to get iOS critical notficiations.
I really hope both of these things change as it wasnāt cheap moving to 9 of these all at once!
Same for me, have 2 new devices in Germany now. Added them to Google Home. But no way to get them to HA. Configured the Google Assistant sdk, but thatās not what I needed.
Target solution for me is to bring the new first alert to apple home.
Any help or solution for that?
With the Nest I went all the why with Nest integration and than with home kit bridge to Apple Home,
Like many others here, my good old reliable Nest Protect Smoke/CO2 detectors (which were fantastic) have all expired. One started chirping every minute - probably due to be expired I assume and I had to remove it. Sadly I have yet to find a solid replacement for them - that is smart, WiFi, and works with Home Assistant. There are several products that seem like they are close to being available like Owl and YoLink, but it seems like things have gone backwards since the original Nest Protects. It drives me nuts that Google bought Nest and then proceeded to destroy them. Any suggestions greatly appreciated.
I have 3 Nest Protect (battery powered) and during renovation I was able to add a wired one. In order to keep the old Nest Protect (that still have may years to expire), I got the First Alert SC5 hopping it would not be crapy (I may be wrong on that based on the comments here), but to make connect to HA, I just got this:
Yes, there are multiple solutions to connect ādumbā smoke detectors to HA, but all they provide is a signal indicating whether the alarm was triggered. While thatās the most important factor, Iād prefer having a device thatās fully integrated. Iām guessing most home automation companies avoid developing this type of device because of the limited demand compared to switches, dimmers, and sensors, as well as the added costly testing and certification required for safety equipment.
I have another year or so in my Protectsā¦ I hope to find something that fully integrates into HA by then. One thing is for sureā¦ I am never going to buy Google hardware again as they always seem to disregard what is best for their customers (quick to EOL, drop support, etc).
That owl product looks interesting, but little details available. Does homekit integration mean that hass will be able to communicate with it? I clicked on the reviews at the bottom of their product page but the wirecutter link doesnāt even mention them, instead saying a different alarm is best, and the āwiredā review is for a motion alarm. I am a bit hesitant because of thatā¦
My nest died today after 9 years, so it is a shame that the tech seems to have gone backwards in a number of ways.
I was just saying the exact same thing, that the tech for the smoke detectors has gone backwards after 10 years. The Nest was a fantastic smoke/CO2 detector and I would be happy with something at least near as good as it was. You wouldnāt think after 10 years this would be an issue, but it 100% is. I would love to see a āNest 2.0ā come back - separate from Google and bring them back.
According to owlās support it works with home assist, but they also say it uses a microwave radar motion sensor to detect smoke?? Isnāt that for motion? Does anyone know what that is about?
Sensors: The Owl Wired is a multi-sensor device that detects smoke, carbon monoxide, motion, temperature, humidity, and noise levels. It uses a microwave radar motion sensor, not photoelectric or ionization technology.
Home Assistant Integration: Yes, Owl Wired can be integrated with Home Assistant via HomeKit. You can read more about it here: Home Assistant Integration.
From AI, CoPilot But, this is only a work around. Iāve not tried this yet, but intend to do so.
Strategy: Monitor the Interconnect Signal
Your wired First Alert detectors use a three-wire interconnect system: hot, neutral, and a signal wire. When one alarm triggers, it sends a voltage pulse (usually ~9V DC) on the interconnect wire to activate the others.
Weāll tap into that signal using a smart device that can detect this voltage change and report it to Home Assistant.
Recommended Hardware Options
Device Type Integration Notes
Zooz ZEN04 or ZEN16 Z-Wave relay Native Z-Wave in HA Can monitor voltage or dry contact input
Shelly Uni Wi-Fi sensor MQTT or native Shelly Detects voltage changes (0ā30V DC)
ESPHome + ESP32 DIY Wi-Fi Full HA control Use GPIO pin to detect interconnect signal
Wiring Overview
Tap the interconnect wire from one of your smoke detectors.
Connect it to the input of your chosen smart device (e.g., Shelly Uni or ESP GPIO).
Configure the device to report a binary sensor to Home Assistant when voltage is detected.
Create an automation in HA to trigger alerts, lights, or notifications when smoke is detected.
Example: Using Shelly Uni
ā¢ Wire the interconnect signal to Shelly Uniās digital input.
ā¢ Configure Shelly Uni to expose a binary sensor via MQTT or native Shelly integration.
ā¢ In Home Assistant, create an automation like:
trigger:
platform: state
entity_id: binary_sensor.smoke_alarm_trigger
to: āonā
action:
@dbCooper - This is the original way of doing it with non smart smoke detectors. The Nest Protect integration exposed all sensors/settings, more than just the alarm that we all hope never triggers . While not absolutely required, it is nice to have them all in HA.
Thinking out loud here, as Iāve got 6 Nest Protectās due for replacement. Could I leave one of the battery powered Protectās tucked away somewhere in the house and use that to integrate into HA? I know I wouldnāt have per-device sensors, but if these will still interconnect with the Protect Iām assuming I could at least get alarming state into HA that way until an integration becomes available.
@MRobi - There are zwave, and maybe Zigbee, devices that can connect to the signal line in order to capture an alarm. This was how it was done before smart smoke & CO detectors. My goal is to nuke the 6 Protects and never buy a Google device again given their poor track record in supporting them long termā¦ so I would not go down that road. I have until early 2027 to replace them so I am keeping my fingers crossed for a comparable !local! (one can dreamā¦) smart detector that doesnāt require Google/Nest or Ring.
Recommended Hardware Options
Wiring Overview
Example: Using Shelly Uni
. While not absolutely required, it is nice to have them all in HA.