What is the purpose of using "Bubble Point" in refrigeration?

Using "Bubble Point" in refrigeration is particularly relevant for calculating sub-cooling. The bubble point refers to the temperature at which a refrigerant begins to boil at a specific pressure. In this context, understanding the bubble point allows technicians to determine the temperature and enthalpy of the refrigerant in relation to the pressure within the system.

Sub-cooling occurs when the refrigerant is cooled below its saturation temperature at a given pressure, ensuring that all the refrigerant has transitioned to a liquid state before entering the expansion device. By knowing the bubble point, technicians can accurately measure how much the refrigerant has been cooled below this saturation state, which is vital for efficient system operation and preventing flash gas formation that can adversely affect performance.

While the other options may relate to refrigeration processes or system performance, they do not specifically focus on the correlation between bubble point and the measurement of liquid refrigerant temperature, which is essential for calculating sub-cooling effectively.