What is the main function of the condenser in an air conditioning system?

The main function of the condenser in an air conditioning system is to remove heat from the refrigerant. As the refrigerant circulates through the system, it absorbs heat from the indoor environment, which transforms it into a vapor. This vapor then travels to the condenser, located outside the building, where it releases the absorbed heat to the external environment.

During this process, the refrigerant undergoes a phase change from vapor to liquid when it releases heat. The removal of heat is crucial for maintaining the cooling effect indoors, as it allows the refrigerant to continue cycling through the system and absorbing more heat, thereby ensuring efficient operation of the air conditioning unit.

Other functions mentioned in the choices serve different purposes within the overall functioning of the air conditioning system. Increasing refrigerant pressure typically occurs in the compressor, expanding the refrigerant is a function of the expansion valve, and filtering contaminants from the refrigerant is typically handled by a filter-drier, not the condenser.