No, they are not connected for alarm sounds and you can not externally trigger the alarms as well.
But since you have Homey, you can play alarm sounds on your smart speakers (and have them say where smoke is detected), add external sirenes, turn on (or flash) your lights, open the curtains, blinds, close gas main, etc, etc…
I recommend frient or develco smoke detector. They work very well and integration is easy.
For these devices: when a smoke alarm is triggered, do they all sound the alarm?
Or is homey able to trigger the alarm?
Dont want to add yet another device (seperate sounder) to the wall. Especially not when the smoke alarm has a sounder.
I only found the popp to support this. (But did not see friend or develco yet)
To be honest it’s very disapointing you cannot trigger them all…
With v2 of the Frient app, you are able to trigger the alarm of the smoke sensor, heat sensor and leakage sensor from within Homey…
Warning: it is creating a hell of noise!
Hello. I’m considering getting the Homey Pro, but am not a Homey user yet. I also want Owl Wired smoke detectors (Matter, HomeKit, Alexa, IFTT and Google compatible). The Owl is a very new product. What is the likelihood that I would be able to control it or utilise Owl’s many sensors via Homey?
Hello,
It should work with Matter sensor devices, but it’s a bit in an early stage.
According to this article below, from sensor types only motion- and contact sensors are supported by Matter itself for now → so I guess only the motion sensor of the Owl Wired should work for now.
Support for other sensors like smoke, air quality is on the roadmap without ETA:
.
That’s a very useful set of articles - thanks! I read about Matter a while back, but I’m impatient and hoped it was further advanced by now. I assume smoke detectors will be last on the list - potentially life-saving devices - so they won’t want to take any risks.
Am I right in thinking that when Matter is ready on Homey Pro, I would be able to connect to Matter devices (such as the Matter-enabled Owl sensor) without having to rely on Homey adding a dedicated app or device to the list of supported devices?
You’re welcome,
Hmmm, I consider any Homey model or/and any wireless device, not suitable to for potentially life-saving devices. Homey is not 24/7/365 reliable, just like any wireless system isn’t. Just my thought on safety.
You’re right, but reading is better than thinking (sorry) 
. It’s in the Homey Matter how to
I really hope it stays like that, to not need any Homey app for standard Matter capabilities
I agree. Luckily I already have a hard-wired smoke detection system in my house, so the Owl Wired is appealing. In theory, the smoke detection element is stable and separate (and hopefully never needed), but the other sensors on the device can be utilised in a smart home system on a daily basis.
Apparently :“Owl Wired has the ability to connect to multiple traditional smoke alarms at a time throughout your house so that you can be informed by phone of smoke in any part of your house.”
As you say, nothing is 100% reliable, but this would give me two ways of being notified when I’m not there: 1. Owl wired connection to the other conventional detectors, and 2. HomePod listening for an alarm sound. The downside is that Owl probably would not be able to silence the ‘dumb’ alarms.
