How is 'Central Air Conditioning' defined?

'Central Air Conditioning' is defined as a system that uses ducts or pipes to circulate cooled air or chilled water throughout a building. This definition encompasses the core function of central air conditioning systems, which is to provide uniform cooling across multiple rooms or zones by distributing cooled air from a central unit.

In a central air conditioning system, the cooling process usually involves the use of refrigerant, which absorbs heat from the indoor air and transfers it outside. The cooled air is then distributed through ductwork or pipes, ensuring effective temperature control throughout the living space. This method contrasts distinctly from other cooling strategies that do not utilize a central unit connected to a distribution system.

The other options describe methods of cooling that do not fit within the definition of central air conditioning. For instance, cooling through open windows relies on natural airflow rather than a mechanical system. Portable devices plug into electrical outlets but do not connect to a ducted system for widespread cooling. Similarly, ceiling fans circulate air but do not cool the air itself, making each of those methods distinct from the comprehensive airflow management system characterized by central air conditioning.