@virtualbitzz Hi, can I ask how to get this firmware and get it working in home assistant?
I reached out to support and they gave me a beta firmware. I’m not sure if it’s gone GA yet. I’m on firmware 9.1.13.1.2.1.
The PR for HA Core has been merged, but hasn’t been released to GA yet, so it’s not working yet, even for me.
This was released in 2025.10.0. hvac_action reporting now works as expected with the new firmware from Meross.
Thanks for making this. I finally got the nest integration working but did not know about the API limitations. So I’ll add to matter and try this out. Thanks for sharing and creating.
So I can confirm that the specific Google Nest Thermostat referenced in this post (the 2020 learning model with the mirror display and capacitive touch bar) can be connected to Home Assistant via the Matter protocol, but cannot be operated 100% locally without an internet connection. I suspect the same for the rest of the Google/Nest thermostats.
The thermostat checks for an internet connection during it's boot process, presumably for provisioning and to apply initial settings. If it can't dial out, all smart functionality (including matter protocol) is disabled and it reverts to acting as a 'dumb' thermostat. Even if you let it boot up with an internet connection, it performs period checks/syncs so once that internet connection is blocked (via firewall or other means) it's just a question of when, not if, the device's matter connection will stop working.
Best guess is that to keep the production cost low and profit margin high, the onboard hardware/software is not capable of handling all the logic of schedules, smart functionality, etc locally so it has enough power to send/receive data from Google's cloud services and update the controls accordingly but not much beyond that and likely all of the matter functionality is being handled via the cloud services as well then simply relayed to/from Home Assistant via the matter protocol. Which is a massive bummer because it means that we're still at the mercy of Google. When (not if) they decide these devices are no longer supported, unless someone gets crafty and creates a custom firmware, or Google suddenly gains a conscience and releases an EOL firmware update exposing basic 100% local matter functionality, these devices become dumb thermostats with no integration possible at best or (probably more likely) ewaste.
It's especially disheartening when the goals of the matter protocol were universal compatibility and fully local control, only for manufacturers to use sh*tty implementations like this. I was incredibly excited when I heard that my thermostats were getting matter support, only to be let down by Google's implementation. I love the look of the Nest thermostats, but when these become EOL I will definitely be looking at ugly bricks if it means I can get 100% local control.
I have 3 Nest thermostats, 2 of which control the A/C's units in my condo apartment and 1 new Matter Nest thermostat in my private garage some 30 floors below my apartment and on a different wifi. All 3 are on the same Google account and all 3 show up in HA, with all the functions. While I use HA for the scheduling of all 3 thermostats, it is also available in the Google Home App.
Right. I'm not saying Matter doesn't work for (supported) Nest thermostats, but it's a stretch to call Google's implementation true 'Matter protocol' because the device still requires an internet connection and registration with a Google account.
If you enjoy being able to use the Google Home app, there is absolutely no judgement - happy for you. But the point of this discussion is being able to use these thermostats 100% locally via Matter and the fact you're using them with the Google Home app means it is not 100% local - they are talking to Google services via the internet and my point is that if you do block the thermostats from being able to connect to the internet (to attempt 100% local control via Matter) they bomb out.
Matter has 2 "highways", Wifi or Thread. The Nest thermostat uses the wifi way. As such it obviously need an router connection. You have to register the thermostat with Google and there is why it needs the internet.