Heating, ventilation, and air conditioning arose from the inventions and discoveries of many scientists, including Nikola Lviv, Michael Faraday, Willis Carrier, Reuben Trane, James Joule, William Rankin, and Nikola Cano.
The components of HVAC systems were invented around the time of the Industrial Revolution, and companies and inventors worldwide have continuously introduced various modern and efficient methods. The three main functions of HVAC-heating, ventilation, and air conditioning-are interconnected, aiming to provide comfortable temperatures and appropriate indoor air quality at reasonable installation, operation, and maintenance costs. HVAC systems provide ventilation, reduce air infiltration, and maintain the pressure relationship between indoor and outdoor spaces or different rooms. The characteristics of airflow into and out of a room are called indoor air distribution.
In modern buildings, these functions (including their control systems, and the design and installation of the systems) are integrated into one or more HVAC systems. For smaller buildings, contractors directly select HVAC systems and equipment based on their needs. For large buildings, the HVAC system is jointly analyzed, designed, and selected by architectural designers and mechanical and structural engineers, and then installed by professional mechanical contractors.
HVAC systems are an international industry, encompassing system operation, maintenance, design and architecture, equipment manufacturing and sales, research, and education and promotion. Previously managed by HVAC equipment manufacturers, the industry now sees significant international management and standardization organizations, including the Air Conditioning, Heating and Refrigeration Institute (ACI), the International HVAC Distributor Management Committee, the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHESE), the American Society of Sheet Metal and Air-Conditioning Contractors (ASEM), the American Society of Air-Conditioning Contractors (ASAC), the Uniform Mechanical Code, and international building codes, all contributing to the provision of services and the improvement of standards within the HVAC industry.