What is the cooling agent typically used in air conditioning chillers?

The cooling agent typically used in air conditioning chillers is water, specifically in the form of chilled water. This is due to water's high specific heat capacity, which makes it an efficient medium for transferring heat away from spaces needing cooling. In many air conditioning systems, water is chilled through a refrigeration cycle, and then circulated through coils to absorb heat from the air.

Chilled water systems are widely used because they provide an effective way to cool large areas and can be used in conjunction with various cooling towers or other heat exchange systems. Water is also accessible and cost-effective, making it a popular choice for both commercial and industrial air conditioning applications.

While chemical refrigerants and compressed gases are indeed used in refrigeration cycles for cooling, they usually only work within the confines of the refrigerant circuit rather than being the effective chilling agent delivered through the space being conditioned. Salt mixtures are not typically used as cooling agents in standard air conditioning chillers.