What is a potential consequence of a clogged evaporator case drain?

A clogged evaporator case drain can lead to water accumulating in the evaporator case instead of draining away as intended. This excess water may overflow and leak into the cabin of the vehicle, causing potential damage to the interior, electrical components, or upholstery. It can also lead to the growth of mold and mildew, which can create unpleasant odors and negatively impact air quality inside the cabin. The function of the evaporator drain is specifically designed to prevent such issues by allowing condensation to exit the system properly, making the possibility of water leakage into the cabin a direct consequence of a clog.