Perhaps a silly question… compressor increases pressure of the superheated gas and increases therefore also its temperature so that the gas becomes hotter than outside and we then can condense with ambient air. Its internal energy increases.
But which phenomena, which natural law let’s the increasing pressure/temperature stops at the condensing temperature pressure? What happens physically in the gas so that it no further increases to a higher level then it stabilise on its high pressure level?
Is it right to say that the ambient air reduces the internal energy whereby the temperature of the gas drops and resulting then also the according pressure?

When the liquid subcools after full condensation, is it correct to say that the dropping temperature while subcooling also lets drops slightly (theoreticallly) its pressure? I never saw this in theoretical books explaining the refrigeration cycle.