Superheat measurements have become increasingly important as energy cost rise resulting in a need for more efficient air conditioning and cooling systems. Superheat calculations are often not done correctly or at all by many technicians. If Superheat is not calculated correctly systems undoubted will be overcharged or undercharged. Superheat is defined as the difference between the temperature at which the refrigerant boils at the given pressure in the evaporator, and the temperature of the refrigerant gas as it leaves the evaporator. In essence, superheat is how much extra temperature the refrigerant picks up after it has boiled. In a worst-case scenario that superheat readings are done incorrectly with an over-charged system and a low indoor heat load, the refrigerant in the evaporator remains in liquid form in the coil and moves into the compressor as a liquid, quickly destroying it.