Connection via wifi and the eWelink app.... despite the fact that it does not have a backlit display, it is a worthwhile product but it does not include any sensor, which of course you have to buy separately.... compatible temperature sensor for solar water heater is the Sonoff DS18B20... I use it with a 12-meter cable extension, without needing to calibrate the measurement, since there is absolutely no difference ... those who have problems with measurement interruptions etc., check the following: 1) poor-quality cable (3 conductors) - I used shielded -, 2) poor-quality cable connections, 3) poor-quality internet connection.

The product is excellent. It connected immediately. I only needed to extend the sensor cable to 5m because the 1.5m was not enough. You should get the THR320D if you want to connect it to the water heater or the solar panel resistance. The 316 is small and it will burn it

I have it connected to the solar, it works perfectly with the sensor and shows the exact temperature, but the only negative is that the app it uses disconnects sometimes but reconnects, within the month it does it 5-6 times but no problem

Excellent for the money and does what it promises. The measurements, as far as I can confirm, are of satisfactory accuracy.

The only downsides are the non-illuminated display and the short length of the sensor cable.

I have purchased several pieces which I use in Fan Coil before their own thermostat for about 1 year now. I would say they are flawless but they have a very small issue with the network losing connection every now and then and needing a restart, but otherwise they are excellent.

I have connected it to the solar panel, it works perfectly and helps a lot. The only downside is that the application it uses disconnects

For the money it is flawless automation in the solar and the cable extended with alarm cable but also with 3x0.5.
Be careful, it is difficult to find a fuse for the temperature sensor.
It is better to connect with another cable

I placed it on a panel to control the water heater. It works very well. It does not handle large loads, but I simply arm a power relay to activate the water heater. The only drawback is that when you are outside the network it is connected to, there is a delay in the temperature display at that time.

Good because you can activate a device if the temperature drops or if the humidity rises, but the disadvantage is that you cannot set an option for both humidity and temperature.
For example, I want a temperature of 18 to 20 degrees and if the humidity goes above 60%, you can choose one of the two, so you need 2 devices

Very useful device. I installed it on the solar water heater. It has a delay for temperature indication of about 30 seconds. It saves electricity for the days when you're not sure if there is hot water or not. I will proceed with other applications for the smart home.

It does a very good job, it also has two relay outputs and you can change the sensor calibration, meaning you can adjust the temperature. Especially with the long cable I have installed, it has been very helpful

In the negatives:
- Firstly, the screen protector is very soft and scratches easily.
- With a 5-meter extension, I do not have consistent signals. Sometimes it measures, sometimes it doesn't.

In the positives:
- Immediate connection to the network

With an extension of the cable 25 meters up to the solar panel with a cable 0.22 X 8 alarm that I had, it worked perfectly fine (I used 3 cables out of the eight)

I bought 2. One for the boiler and one for the solar panel. I installed the ds18b20 temperature sensor from Sonoff on both, along with a 5-meter and two 15-meter extensions respectively. The result is that after 31 degrees Celsius, I don't have any temperature indication. After some research, I found out that the extensions are to blame, despite Sonoff stating that it can handle up to 60m of extension. Anyone who wants to install it should know that it only works properly with the 30cm cable of the ds18b20. The solution I found is to use another sensor and connect the necessary wire, but I haven't tried it yet. I will update when I do. 2 stars with leniency! EDIT: In the end, I bought the new Sonoff WTS01 sensor from an international website, which works perfectly.