At which component does the refrigerant reach its lowest pressure and temperature?

The refrigerant reaches its lowest pressure and temperature at the evaporator orifice inlet. In the refrigeration cycle, as the refrigerant expands through the expansion valve, it experiences a significant drop in pressure. This reduction in pressure causes the refrigerant to cool, reaching its lowest temperature as it enters the evaporator. The evaporator is where the refrigerant absorbs heat from the surrounding environment, causing it to evaporate into a gas.

In comparison, the compressor pressurizes the refrigerant, raising both its pressure and temperature, while the condenser allows the refrigerant to release heat, which results in a higher temperature and pressure as it transitions back into a liquid. Therefore, the evaporator orifice inlet is the point in the cycle where the refrigerant is at its lowest energy state, making it essential for the cooling process.