The top pipe is submerged, and the other pipe is a simple valve. As the volume inside the container cools, the air pressure reduces, since the pressure of air outside the container is connected to the volume of water underneath, the pressure of air pushes the volume below and that squeezes the water past the valve at the top.
The pressure from the column of air at the top pipe is not sufficient to overcome the volume of water in the closed container, and so remains neutral.
That's the best I can describe this effect for you. ChatGPT would probably do a better job.
The pressure from the column of air at the top pipe is not sufficient to overcome the volume of water in the closed container, and so remains neutral.
That's the best I can describe this effect for you. ChatGPT would probably do a better job.