All of us have felt the relief of entering a building or home with artificial cooling that balms away summer heat. The technology behind this marvel is the self-contained air conditioner and understanding their working principles can help you find the most energy-efficient solution for any space. An Air Conditioner (AC) is defined as a device used to regulate temperature and humidity in an enclosed living or commercial space to keep it comfortable for inhabitants. To be labeled as ‘self-contained’, an AC must have all major components built into one unit, not reliant on any other units for additional parts or necessary functions. Self-contained air conditioners are a great way to cool spaces with limited available space and no ductwork making them popular solutions in places like apartments, offices and university campus dorms.