In a refrigeration system, what is the purpose of a compressor?

The purpose of a compressor in a refrigeration system is to increase the pressure of the refrigerant. As the refrigerant enters the compressor in a low-pressure gaseous state, the compressor compresses this gas, which simultaneously raises its pressure and temperature. This process is essential because the high-pressure refrigerant is then able to flow through the system to the condenser, where it releases heat and changes state from gas to liquid.

Understanding that the compressor's primary role is to elevate the pressure helps clarify its function in the refrigeration cycle. Compressing the refrigerant is critical for achieving the necessary conditions for effective heat exchange within the system. It enables the refrigeration process to continue efficiently by ensuring that the refrigerant can absorb heat from the space being cooled when it evaporates in the evaporator coil.

Other options, while related to functions in a refrigeration system, do not accurately define the compressor's primary role. For instance, while the system does circulate the refrigerant, this action is not solely performed by the compressor but also involves other components like the condenser and evaporator. Similarly, cooling or heating the refrigerant pertains to different phases of the refrigeration cycle, where specific components handle those temperature changes after the refrigerant has been pressurized by the compressor.