Below is a list of Chiller System manufacturers from St. Louis, Missouri. Chillers are liquid refrigeration systems that cool commercial buildings, manufacturing facilities, products, machinery and industrial processes. They use water, oil, brine, alcohol, ammonia and halocarbons as liquid or air coolants. While they vary considerably in design, size and ability, all chiller systems are composed of 4 main parts-a compressor, evaporator, condenser and metering device.