A dual (or multi) sectional evaporator system comprising first and second (or more) evaporator sections capable of cooling the air supply through the evaporator. The first evaporator section is positioned upstream of the second evaporator section (second upstream of the third and so on). However, the warmest refrigerant passes through the first evaporator section and the coldest refrigerant passes through the second evaporator section (or last evaporator section if more than two sections), such that the air supply is precooled prior to reaching the second (or last) evaporator. Providing a two (or more) passes of refrigerant through the dual (or multi) sectional evaporator system increases the superheat temperature out of the first evaporator up to about 25 degrees Fahrenheit, and/or increases the mass flow of refrigerant because of the increased heat exchange efficiency provided by counterflow heat exchange. Moreover, in the preferred embodiment for an A-coil or slant coil, the second evaporator section is positioned over the top of the first evaporator section such that the second evaporator overlays the first evaporator section in order to maximize the use of available space. Also, A-coil or slant coil forms of the present invention are configured such that they include contoured cut-out shaped corner portions wherein the squared corners of the evaporators are substantially eliminated thereby eliminating the dead air flow spaces typically associated with other known evaporators. The elimination of the dead air space allows the system to operate at a lower fan speed as well as allows the system to be constructed and operate within smaller confines.