Trying to understand refrigeration through statistical mechanics (i.e. what happens to each molecule), as you are trying here is going to be a bit tricky. Refrigeration is really best explained by classical thermodynamics, using properties of the fluid like enthalpy, pressure, entropy, etc. which themselves can be understood using statistical mechanics. As a matter of fact, the vapor-compression cycle was invented before Boltzmann's theory.
Two significant mistakes in your diagram:
My advice for understanding the vapor-compression cycle:
The compressor and the valve are there to enforce this pressure differential between the hot side and the cold side.
Thanks much for the brainpower! Agreed that this is easier to think about in terms of classical thermodynamics with its continuous fluids; I'm just on a bit of a stubbornly fundamentalist kick (ex).
If it entertains you to continue chatting, I have a couple clarifying questions:
They are in an environment where the pressure is low enough that [the droplets] can vaporize [...] the system is a vapor+liquid saturated equilibrium.
"Saturated equilibrium" sounds at odds with "pressure low enough that the droplets can vaporize." Reconcile? (My best guess: you...
In terms of looks would look better as a cycle (like in circle or some rounded square). It would also be conceptually closer to what is happening, as the actual mechanism is a cycle.
This Technology Connections video on heat pumps made me realize I don't intuitively understand how refrigeration works. I tried to drill down until I understood what was happening with every molecule, and... arrived here. Would any local thermodynamics experts enjoy pointing out the important gaps?