What is the purpose of refrigerant in an HVAC system?

The purpose of refrigerant in an HVAC system is to absorb and transfer heat. In cooling systems, the refrigerant circulates through various components, including evaporators and condensers, undergoing phase changes from liquid to gas and back. This phase change allows the refrigerant to absorb heat from the indoor space when it evaporates (turns into a gas) and releases that heat outside when it condenses back into a liquid. This heat absorption and transfer process is critical for maintaining desired indoor temperatures and ensuring the overall efficiency of the HVAC system.

The other choices do not reflect the primary role of refrigerants in HVAC systems. While air cleaning and filtering out pollutants can occur in various parts of an HVAC system, they are primarily the functions of air filters and purifying devices, not the refrigerant itself. Similarly, increasing air pressure is not the purpose of refrigerant; instead, it is managed through the blower and ductwork of the system.