To create lower temperatures indoors, your air conditioner uses the circulation of refrigerant, a chemical compound that can easily change between liquid and gaseous forms. As the refrigerant evaporates in the indoor coil of the AC, it absorbs heat and makes the air cooler. Then the refrigerant condenses in the outdoor coil, which releases the heat to the outside. This process is called heat exchange, moving heating from one place to another.
Without refrigerant, an air conditioner cannot carry out heat exchange, and that means no cooling. But that’s not the worst part! Without the proper amount of refrigerant, the entire AC is in danger of failing—usually permanently.