Honeywell thermostat - thermostat turned off, the heater turns on when the window is open

Hello,
Above, when I tilt or open the window to ventilate the apartment, the Honeywell thermostat, set to 0, automatically opens the flow of hot water to the radiator. And this is the problem: I`m in the middle of renovation and I need to air the apartment more often. Could any of you give me advice on how to block/switch off this automatic heat flow? I will add that I only have this problem in one room.
The plumber from the cooperative has already been there five times and claims that nothing can be done, but when I asked why this doesn`t happen in other rooms, he couldn`t answer. Within three weeks, the reading on heat allocators increased by over 100 units.

You set it to 0 or an asterisk, what is the temperature of the air entering through the window, and whether the head is in a draft.
look for installers, maybe one of them has a valve cap, so during the renovation you can remove the head and put on the cap and make a regular valve.


Here is a sample catalog note

I set it to 0, the head is under the windowsill, the window is ajar, not wide open. The temperature in the apartment is 20 degrees and above (I wear a T-shirt), the block is insulated, the walls in the apartment are plasterboard. Outside air temperature - as outside in the current weather. I will also add that my apartment is on the top floor, but on the south side, so it is always warm and sunny.
Thank you for the advice, I will try to buy this valve cap somewhere.

If the temperature in the apartment is +20 degrees and when the knob is set to "0", the radiator turns on when the window is open, the head is probably defective. With the "0" setting, the radiator is usually turned off even at a very low room temperature (the * setting means it is turned on when the room temperature drops below 5 or 6 degrees, depending on the brand of the head and is intended to prevent the installation from freezing). Currently, the temperatures are not too low yet, so even if the head was located outside (i.e. outside the room, in the open air), it should close the heating in the "0" position. Yes, you can replace the head with a cap during renovation.

Thank you for your answer. Does this mean that I should apply to the cooperative for a head replacement? For now, I covered the head with a small thermal bag, tightly closed and... it works. In any case, this solution does not satisfy me, so starting tomorrow I will start another battle in the cooperative.

Hello
As my friend wrote, try the cooperative, but from what I remember, the valves were leaking and the cooperative repaired it, but nothing happened to the heads.

Closing the thread: I wrote a letter to the President of the Cooperative and the heads have already been replaced. Thank you for all your help