What does the term "subcooling" refer to in commercial refrigeration?

Subcooling refers to the process of cooling a liquid refrigerant below its saturation temperature, which is the temperature at which the refrigerant would boil at a given pressure. In commercial refrigeration systems, subcooling is important because it ensures that the refrigerant entering the expansion valve is in a fully liquid state. This helps improve system efficiency, as liquid refrigerant will absorb heat more effectively in the evaporator.

Achieving sufficient subcooling can also help prevent the formation of vapor bubbles in the liquid refrigerant line, which can prove detrimental to the system's operation and efficiency. In essence, subcooling enhances the overall performance of refrigeration systems by optimizing the refrigerant properties as it cycles through the system.