What is the primary function of a chiller in an HVAC system?

The primary function of a chiller in an HVAC system is to remove heat from a liquid, which is typically water or another fluid that circulates through the system. By achieving this heat removal, the chiller effectively lowers the temperature of the fluid, which can then be used for cooling spaces or for specific processes that require temperature control.

In HVAC applications, the chilled liquid is often circulated through coils or other components to absorb heat from the air or materials in the environment. As the chilled fluid passes through these areas, it absorbs heat, which leaves the surrounding space cooler. This process is crucial for maintaining comfortable indoor temperatures in large buildings or industrial applications.

The other options do not accurately represent the main role of a chiller. While increasing humidity levels is related to other components in an HVAC system, such as humidifiers, it is not a function of a chiller. Similarly, controlling air pressure and filtering particulate matter are functions associated with other elements in HVAC systems, such as fans, ducts, and air filters, rather than chillers. Thus, the correct understanding of a chiller's role focuses on its heat removal capabilities, aligning with its fundamental purpose in HVAC systems.