Fieldpiece introduces the first Diagnostic Psychrometer that not only performs the normal functions of a digital psychrometer (DB, WB, RH%, DP), but also helps technicians analyze air conditioning systems. Using normal psychrometer measurements, the SRH2 calculates Target Evaporator Exit Temperature (TEET) and Target Superheat (TSH). The technician needs TEET to properly adjust air flow across the evaporator. He needs TSH to properly charge a fixed orifice A/C. See for more on the SRH2.