What happens to the mass pumped by the refrigeration compressor due to the pressure drop in the intake valve.

Due to the pressure drop in the inlet valve the mass of steam pumped by the compressor tends to decrease. This occurs because the inlet pressure inside the cylinder is less than the pressure in the suction line (due to pressure drop in the intake valve) causing an increase in the specific volume of the vapor inside the cylinder, decreasing the amount of mass that consequently enters.