In most HVAC systems, humidity can be controlled in order to maintain a comfortable environment. Your HVAC System’s evaporator coil condenses water vapor, or the water vapor that evaporates from a room, in a process akin to the condensation on the outside of a cold beverage glass in the summer. When your home’s hot, humid air comes into contact with the cold evaporator coil, this can lead to a situation in which condensation occurs. It is then the liquid in the air that condenses out, making your home less humid as a result. As a result of the evaporator coil collecting moisture, it is sent to a drain which is then sent outside, away from your home or office building, where it can be drained.