When people first encounter the term chiller (if they don't first think of a scary movie) they usually think of something that creates cold or cools the surrounding air like an air conditioner or the maybe even a refrigerator. This is a bit misleading. A chiller consists of the following six main components: Evaporator-cools the water, water/glycol or air by transferring the heat to a refrigerant which is turned into a gas. Compressor-takes this gas and increases its pressure so that ambient air or water can remove the heat.