Which of the following is NOT a function of a compressor?

The function of a compressor primarily includes augmenting the pressure of a gas or vapor and facilitating its movement within the refrigeration or cooling system. In this context, compressors serve as pressure imposing elements, effectively raising the pressure of refrigerants to facilitate the refrigeration cycle.

A compressor is also driven by a prime mover, such as an electric motor or an internal combustion engine, which provides the necessary mechanical energy for the compressor to operate. Additionally, some compressor designs incorporate elements akin to a centrifugal pump or screw pump in that they compress and move fluid, albeit this is more about their operational nature rather than their primary purpose.

In contrast, a heat exchanger serves a different role within the refrigeration cycle by transferring heat between different fluids without mixing them, which is not a function performed by a compressor. The primary function of a compressor is not to exchange heat but to increase the pressure and help circulate the refrigerant, making "heat exchanger" the correct response to which is not a function of a compressor.