I’m getting ready to get a new thermostat for our home. Which thermostat would provide me with the best integration for Home Assistant? I was going to just get an Ecobee; since that seems to be very popular.
Do all Thermostats require cloud access? I don’t want a thermostat that will not work if Internet is down, if possible.
I was using Nest for years but since Google took over the API has been really bad, and breaks constantly in HA. I switched to the Honeywell T6 which requires no cloud access and I’ve been pretty happy with it so far.
Did you get the wifi version of the thermostat or the zwave version?
You have to define what you mean with most compatible.
Do you want them to be directly integrated into HA, like Zigbee or is through an integration also fine?
Do you want to have thermostats that have no intelligent code, so you have to make you own logic in HA (which means HA have to run for anything more than just hitting the target temperature) or is a built-in intelligence a must and is it okay if it can’t be disabled or do you require this to be possible.
The built-in intelligence can be tricky when you want to use it with thirdparty external sensors, like a room thermometer.
Personally I use a Homematic IP setup and I am quite happy with it.
It needs an integration and also an addon, but it is completely local.
It has intelligence built-in that can’t be disabled, which I have to “fight” when I make my own logic, but it is possible (the Better Thermostat integration can provide the code to do the fight and implement a thirdparty sensor with ease).
I use Homematic IP external thermometers too and could actually just hand over the control to the system, which is quite good. I just thought I could do a bit better. 
The question is if Homematic IP is at all available in your country. It is a German product and mostly European sold.
Thanks for the reply. I’m looking for a popular thermostat brand with it’s own Home Assistant integration.
It doesn’t have to be 100% local. As long as I can still control the temperature if the internet goes down.
I can either use wifi, z-wave , zigbee. However, prefer just plain wifi connectivity when setting it up.
I have an Ecobee and I use both the cloud integration and through HomeKit. The cloud integration only updates every few minutes, so you won’t see a change right away. However, the cloud integration is the only way to see the “Comfort Setting” if you added any beyond the built in Home, Sleep, and Away settings. I have a Morning and Evening setting, so I use the cloud integration for determining which comfort setting is active.
For everything else, I use the HomeKit integration with the thermostat. I see nearly instant changes to temperatures and settings. This is the primary way I pull info from the thermostat. And since it’s HomeKit, it’s local.
I got the Z-Wave version, it’s been solid. There are a few minor pecadillos but there’s an easy automation to handle that, it’s just that sometimes it doesn’t report back the temperature right away but I’ve only had it happen once and since implementing the automation it’s perfect.
Can you tell me which specific Honeywell model you bought? Which specific Honeywell Home Assistant integration did it use? Do you know if the wifi version also doesn’t require cloud access? I have both zwave and wifi… but, if I had to choose, I’d probably prefer wifi.
Honeywell is not Homematic IP.
It might be by the same manufacturer (or a whitelabel there of).
I use Debmatic and the (now) official Homematic_local integration.
Most will probably use RaspberryMatic instead of Debmatic, but that is really little difference, since it is the same ported firmware from the official local Homematic CCU that runs in both cases.
Homematic IP is a 868MHz RF product series. It has it’s own protocol made with battery powered devices and response notifications in mind, which works pretty good, IMHO.
The protocol even allow for device-to-device communication, so even when the hub/addon is down the external thermometer can communicate with the thermostat and control it.
I only use the heating products (thermostats, thermometers and door/window sensors), but there are more areas in the series and new seems to be coming regularly.
@CO_4X4 It seems like many people are going for the Honeywell T6. So just to be clear, you don’t need Homekit or anything like that… just zwave and Home Assistant?
Is this the one I should get or is there a newer one?
Amazon.com: Honeywell TH6320ZW2003 T6 Pro Series Z-Wave Stat Thermostat &, Smart Home : Tools & Home Improvement
Long-time Ecobee user here. It’s great, except when it’s not. Their customer support is painfully slow to respond to e-mail messages. When the thermostat drops wifi (like during a weekly router reboot) they often will not reconnect. Only removing the thermostat from the wall and power and forcing a hard reset works. It’s a shame, really. Their UI is great, their phone app is great, the technology is great. Their support? Bad. Their wifi connectivity? Bad.
Thanks. This further motivates me to get the Honeywell T6 Z-wave.
Z-Wave is a certified protocol, which means products needs to be tested at a certification center to prove that they adhere to the protocol in every way.
This makes the products a bit more expensive, but the products generally works without any hiccups at all.
This also means that the HA integration is easy to make complete for the protocol and all products can be implemented before hand.
I have a couple of Venstar T7850, which are packed with features including remote sensor support. The integration uses local polling over WiFi and brings a ton of entities, even the temperature of each remote sensor. No cloud dependency at all.
The devices are not as stylish as others, but get the job done pretty well.
Correct, and the one you linked is the right one. No cloud needed for that, or the WiFi, but I can’t speak to the WiFi’s usability, as I only have the Z-Wave.
Honeywell T6 user and have had no issues. My heating/cooling automations use the temperature from several sensors on each floor to control it.
I saw some guy in another thread complaining about losing some programming ability on the T6 itself when using z-wave. Stuff you can easily do in home assistant, so I dont know why he was complaining about it…
I use a Netatmo smart Thermostate. Works fine for me.
Thanks for your response. From what I’ve found by searching here and what other people are saying, The Honeywell T6 zwave is the one I want.
Ever since the native ZWave integration went away and the release of the new Zigbee-only Sky connect dongle, I was starting to worry that people are moving away from ZWave; despite it providing better range and mesh networking capabilities.
Ever since the native ZWave integration went away (switched to zwave-js add-on) and the release of the new Zigbee-only Sky connect dongle with Thread and Matter support, I was starting to worry that maybe people are moving away from ZWave; despite it providing better range and mesh networking capabilities. I’m hoping that there will be a manufacturer that releases a good Zigbee+zwave combo dongle with Thread and Matter support for me to upgrade from my HUSBZB-1 dongle.
It’s still looks fancier than the Honeywell T6 zwave thermostat which has a monochrome screen.