What is the expected state of the refrigerant in the suction line?

The expected state of the refrigerant in the suction line is low pressure, low temperature vapor. This condition occurs because the refrigerant has absorbed heat from the indoor environment in the evaporator coil, causing it to evaporate into vapor form. As it travels through the suction line, the vapor maintains a low pressure and temperature due to the expansion process that occurs within the evaporator.

In a refrigeration cycle, after the refrigerant absorbs heat, it completely transitions into a gaseous state. This vapor then makes its way back to the compressor through the suction line, where it is at a lower pressure compared to other points in the system, particularly after passing through the expansion valve. Thus, the characteristics of low pressure and low temperature are typical of the refrigerant in this section of the system, enabling efficient operation and preparing the refrigerant for compression.