THIRDREALITYZigbee Temperature and Humidity Sensor Lite,Smart Thermometer and Hygrometer, Hub Required,Compatible with Echo Devices with Zigbee Hub Built-in,Home Assistant,SmartThings,Homey,Hubitat

I have a Home Assistant server running at my house that controls a variety of devices and services (e.g. lights, switches, valves, etc.) and wanted to add temperature sensing.My old sensors from a different brand used Bluetooth Low-Energy, but their short-range signal couldn't reach the server (I had to use their phone app, which was not ideal).I had previously installed a Zigbee mesh network for several devices, and adding these Zigbee sensors to that network was simple: tell the Zigbee coordinator to look for new devices, insert the batteries into the sensors (or push and hold the button in the sensor for 5 seconds to enter pairing mode), wait 30 seconds, and they're good to go. I use Zigbee Home Automation (ZHA) and it got them set perfectly.The measurements are accurate (they match reality, as determined by other sensors I've previously calibrated) and precise/consistent (the Third Reality sensors all agreed with each other within the specified accuracy).For testing purposes, I moved several of the sensors around to different areas of the house and after a few hours they realized that there was a closer Zigbee router with stronger signal and automatically switched to connect to that, better signal. Certain other brands of sensors like "lock on" to a single router and if that router ever goes offline or they lose signal from it they never try to find another router on the network. That's not an issue with these sensors.Pros:- Simple: there's one button to put the sensor in pairing mode, and an LED that flashes to indicate when it's in pairing mode.- Checks for better signal/routers and will switch as needed. (That is, it's a good member of the mesh network.)- Accurate temperature and humidity readings.- Reliable data transmission. With the exception of the few times I rebooted the server or disconnected the Zigbee coordinator for testing purposes, the data from the sensors has been reliably sent to the server without issue. Several sensors were within a few feet of a WiFi hotspot (WiFi can sometimes cause interference with Zigbee since they share the 2.4 GHz band) and worked without any problems.- Use standard AA batteries rather than costly coin cells.- In addition to sending temperature and humidity data, they also send their battery charge level. Setting up an alert in Home Assistant so one knows when to change the batteries is recommended.- Very power efficient. Two AAA batteries should give years of service.Cons:- No option to calibrate the sensor. (While the sensors on mine are accurate, it would be nice to have an option to send calibration commands to them to correct for any error.)- No loop or other means of mounting or hanging it somewhere. My Bluetooth-based sensors are hung from a short string in the air in their various locations so they only measure air temperature and aren't influenced by sitting on a shelf or something. These sensors don't have a hole for threading a string or lanyard.

This 3R temperature and humidity sensor was quick to setup and works great on my SmartThings smart home network. I initially placed the sensor close to a digital thermostat to test its accuracy against a device I have trusted for years to provide room temperature and humidity. I found the 3R sensor accurate and only required a small adjustment to the settings for the device within the SmartThings app. The settings within SmartThings are straight forward; you don’t need a programming degree or the ability to read the programmers mind to figure out the needed adjustment. Just a simple negative or positive number to adjust both the temperature and humidity. I also found it quick to adjust to environmental changes in my home.

Edit: I stand corrected! It appears that my connection issues previously mentioned were due to interference with the Zigbee hub antenna. After several changes in orientation, and position, signal levels and stability are greatly improved. If I had any other complaint, it would be that when a sensor loses connection, you have to phyisically go to the sensor to reconnect it. This may be more of a Zigbee thing rather than a device issue, but for several of my sensors, this is a real pain. Hopefully after the recent changes, this won't be a problem.Units connected easily and seemed to function well. Problem is that out of 6, 3 have lost connection at least once. After some "fiddling", they can be reconnected but very annoying. 2 of the 3 that lost connection are the closest ones to the Zigby antenna. One literally about 15ft away has lost connection twice. Firmware is at latest revision. 3 have had no issues but 50% reliability after a few weeks won't cut it.

I have a Home Assistant instance setup with ZHA, and this has by far been the best temperature sensor I've found. It pairs quickly and has no issues within the network. It's reported values are where they should be based on the stated tolerances of the sensor, and the fact it uses standard AAA batteries is a huge bonus.

using it in my bathroom to automatically turn on/off the exhaust fan when humidity hits a certain threshold. not sure how accurate it is but for my use case it's not important. will likely get a few of the sensors with screens for other rooms in my house and hopefully sync them to my thermostat to adjust depending on the averages.

The sensor is a bit large, but very well constructed. It comes with two installed AAA batteries and is ready to be paired. I paired it very easily to my Home Assistant Hub. It reports temperature, humidity, and battery percentage. I plan to use it outside under the roof eves to keep track of the outside temperature.