Water drainage characteristics (Mathur, 2016) of an evaporator changes with the age of the vehicle. This is due to the fact that with time, a part of the hydrophilic coating washes off with the moisture that condenses over the evaporator core from the air-stream. Hence, the effectiveness of the water drainage deteriorates. At this condition more water is retained in the evaporator as the contact angle increases. Author has conducted experiments with evaporators taken out of the vehicles with its AC system operated for 6 months, 12 months, 18 months, 24 months, 36 months, and 60 months. Evaporator cores from many suppliers (A, B, C) were used for this investigation. Evaporator cores were recovered from low (Phoenix) and high humidity areas (New Orleans, Houston, Jacksonville). These evaporators were analyzed to determine the effectiveness of the hydrophilic coating as a function of time or vehicle age. Evaporator plate and fin design also have significant influence on water retention in the cores. However, this investigation strictly focuses on the hydrophilic coating for existing evaporators. This investigation will be one of the most exhaustive investigations to date that will be available in the open literature. REFERENCES Mathur, G.D., 2016. Experimental Determination of Effectiveness of Hydrophilic Coating for Evaporators, SAE paper # 2016-01-0191.