Obviously, the device I bought was defective. It sent a signal to the burner for 20 seconds every 2-3 minutes. In some cases, it didn't send a signal at all even though there was a 1-degree difference with the room temperature. Nevertheless, Skroutz informed me that this is how this thermostat works because it seems to be smart. If you want the burner to turn on and off continuously, then this is the right thermostat for you!
P.S. This is how the thermostat has been working for about a year, so whatever it was supposed to learn, it has learned.

My unit did not adjust the temperature as another review mentions. My observations are:
1) Comparison with the top Honeywell Aube regarding the measured room temperature. Exactly the same.
2) The relay for the command is 125VAC. If your load is at 230VAC and high current for a long time, it will not withstand it. If your system simply expects a closed contact as a command, no problem.
3) There is no hole at the back of the box to pass a bipolar NYA cable, but you have to separate the two wires and pass them through the small holes at the back.
4) As with almost all thermostats, the relay is mounted on the wall base while the board is detachable. The connection is usually made with a plug-in terminal. However, in this thermostat, it is done with two spring-loaded pins that make contact on two round pads on the printed circuit board. It raises a question about the reliability of this connection method over time.

I give it 4 stars due to the above observations.

But in the apartment where it was installed, the tenant is thrilled. She mentioned that it seems like the gas burner doesn't work much, but the space consistently maintains a stable temperature.

P.S.: A proper thermostat can reduce energy consumption by up to 50% in a home.

First time I encounter a thermostat that raises the temperature on its own. I set it to 20 and it goes up to 23 on its own and doesn't shut off. What can I say now..