Pearl Thermostat (Works with SmartThings, Spectrum, Cox, Time Warner Cable, Vera, and ZigBee Platforms), White

I was a bit all over one this one... The first one I got was off by 2F when I first installed it. I understood this wasn't a big deal just a bit of error. After a day that gap increased to 3-4F seeing some other reviews this worried me about the longevity of the device, so I asked Amazon for a replacement. I installed the replacement and it was within 1-2F of other thermometers I have nearby. After 24 hours, I noticed that the gap was really 1.4F, so I used the temp calibration option in the settings. I have been keeping an eye on it for about a week and it seems to be correctly doing what a thermostat is made to do. I am planning on buying a few more in the near future!The wire terminals for the thermostat are really weird. I haven't seen this style before, so I didn't realize that you have to pull the tab and insert the wire at an angle to get it to lock in place. I much prefer other designs.Some notes about home assistant:First of all... it works great with home assistant. It was picked up as soon as it turned on, and home assistant created a card with the basic functionality. I also love the ability to see a chart of the temp changes with what action the thermostat is doing. It should be trivial to calculate the heatloss of the home with this information.Thermostats require different thinking than plugs and light bulbs. A thermostat is an external device that does its own thing. You put it into a state (cool/heat) and give it a desired temp and the thermostat does the rest. I was thinking I would tell it "run cool for 5 minutes", but to do that you would have to say "set the target temp 2F lower than the current" I also wanted to tell it to turn on the fan only for say 10 minutes if it is cooler outside instead of using the AC unit. To turn on the fan only mode from home assistant apparently you have to call a service to set the HVAC mode to "fan_only" this has to be done in yaml editor not from the web gui. I was able to get the fans only to run, but I couldn't get it back into the cool state, so I manually pushed the mode to cool from the device itself.There is a little delay to get the thermostat with a change, so don't expect immediate response. It seems to take 1-3 seconds, so not bad but if you are trying a few things at one time have to give it some time.Sometime the thermostat won't update for some time. Watching the home assistant website I have seen where the device hasn't sent an update for 1 hour. I even walked over to the thermostat to read the temp it shows. Every time I have done this, I noticed the temp is the same as the room. My conclusion is that the temperature hasn't changed enough to warrant sending an update to home assistant. This seems to be normal activity for temp sensors with zigbee.Overall, I have never paid so much attention to thermostats. Having it patched into home assistant made me realize how little I understood how they work. For example, I can see the swing temp in action... the house's temp gets 1.2F above the target it will turn on the AC to lower it to 1.2F below the target. In home assistant I can see it cycling around this temp...it's really cool.

The thermostat is quite good overall. It comes with support for all kinds of different setups, such as heat pumps with auxiliary heat, resistive electric, gas, etc. The display looks decent enough to me, but I know some people will be upset about the blue LEDs. I do wish there was some sort of option to hardwire it, so that it could become a Zigbee router, rather than just an end device, but that's very much a nice to have.Theres really only one very minor issue I've experienced. Issuing multiple updates in a short period of time to the thermostat through Zigbee won't always take immediately. The first update will always work, but issuing more seems to overload it or something, and it can take a little bit before it responds to the queued commands. This isn't a huge problem though, as manually operating the physical controls always works immediately.The only reason I discovered this at all was because I was programming some custom automations with home assistant, and was intentionally turning the heat on and off, many times per minute. In normal use, you won't be changing the target temperature 20 or 30 times at once, so this is not a real issue.

Buy this if all of the following are true:- You have a ZigBee-capable hub (SmartThings/etc) or ZigBee USB Stick/home automation software (Home Assistant/etc ... mine worked out of the box with the Nortek GoControl Z-Wave/ZigBee USB stick (firmware updated ZigBee) and Home Assistant)- You don't care about the thermostat, itself, having features beyond "set temperature/humidity/heating/cooling" with compatible heating system(s)- You do or don't have that "Common" wire that only newer installations have (it's not needed, though others have complained about batteries not lasting terribly long).This was the least expensive "smart" thermostat available on the site when I purchased it a couple of days ago. I have no interest in a Nest/EcoBee, I've got my own setup and they're over budget for me.I also leaned toward Z-Wave/ZigBee instead of WiFi since the wifi units in my budget appeared to have similar problems to other lower-end IoT devices, but the cost of Z-Wave/ZigBee thermostats are quite high despite them generally being not very interesting. On the WiFi side, there's plenty, but they're all more than this, all use cloud services so I have to worry about the provider quitting/failing and me losing remote control of my thermostat (minor, yes, but I paid for it). Then there's this one... no cloud, ZigBee, inexpensive, looks better than every other one within $40 of its price tag.Setup was *simple* -- pairing with ZigBee was simple, I just set the device to "add" mode, plugged the thing in and it showed up. Mark the wires, take the old one off, put the new wires where the old ones were, screw it into the wall/pair and done.Two extra points for getting a couple of things right that the cheaper models don't:- It looks nicer than the pictures. In fact, it looks "expensive" (certainly more expensive than it was). The front panel doesn't feel like cheap trash like most thermostats; it falls way short of the sleekness of an EcoBee/Nest, but the thermostat isn't meant to be a conversation piece.- They either nailed the temperature, or I got lucky. This is within a few tenths of my most accurate ambient temperature sensors. Knowing that most thermostats have pretty terrible sensors in them, I planned on triggering the heating/cooling based on other, more accurate, sensors in my home.Bonus: The temperature being reported by the unit is better than the higher-end one I replaced it with. It's a few tenths off, southward, at least at the current temperature. Since my other was two whole degrees (Fahrenheit) off, that's an improvement, but it's also moot since I'll be triggering the thing based on readings from multiple, very accurate, sensors. If it's this accurate all around, I'll probably include it in the values- The super-short manual was readable, but unnecessary. It's a simple installation.