Two DX air cooling coil modeling methods, one used in EnergyPlus and the other termed as a generic rating-data-based (GRDB) DX coils modeling method, were summarized and their detailed calculation procedures were presented using one case study. Six rooftop models of two manufacturers were used for this study to predict sensible cooling capacity. It demonstrated that the relative errors in sensible cooling capacity prediction ranged from -14.9% to 15.1% for the method used in EnergyPlus and from -7.4% to 4.2% for the GRDB method. In addition to higher accuracy and precision, the GRDB method is more robust against the variations in parameter selections, has a wider application range, requires less computation power, and is more straightforward.