Air conditioners keep you comfortable by removing heat and moisture from the air. To do both effectively, the unit must be properly sized for your space. If the capacity is too low, you may never feel quite cool enough. When the capacity is too high, the unit produces so much cold air so quickly that the room reaches the desired temperature before the unit has adequate run time to dehumidify. The result is a cool but clammy room that can feel just as uncomfortable as one that is not cool enough.