Thermodynamic Wet-Bulb Lines. For ASHRAE’s chart, only thermodynamic wet-bulb T * lines are shown. Since the dry-bulb and the thermodynamic wet-bulb temperatures coincide with each other on the saturation curve, one end of the T * line is determined. The other end of the T * line can be plotted on the w line where w 0. Let the state point of the other end of the T * line be repre- sented by 1. Then, from Eq. (2.39), at w1 0