A method for tuning refrigerant charge in modeling off-design performance of unitary equipment (RP-1173)

In this paper, a method for adjusting refrigerant charge is presented. it uses a charge correction equation that requires data for two operating points for parameter tuning. The two-point charge tuning method leads to much better prediction for a wide range of operating conditions and regrigerant charge levels. That method has been tested for multiple units and worked well..