Heating，Ventilation and Air Conditioning

Heating, Ventilation and Air Conditioning (HVAC) refers to the indoor or car is responsible for heating, ventilation and air conditioning system or related equipment. The design of HVAC system is applied to thermodynamics, fluid mechanics and fluid machinery. It is an important branch in mechanical engineering. The aim is to establish an artificial environment conducive to human survival. And sometimes in the abbreviation HVAC by adding R, on behalf of refrigeration (Refrigeration), the abbreviation becomes HVAC & R or HVACR, or abbreviation to join R, minus the representative of the ventilation V, the abbreviation becomes HACR. HVAC system can control the air temperature and humidity, improve indoor comfort, large and medium-sized industrial buildings or office buildings (such as skyscrapers) in an important part. In the pharmaceutical, electronics, mission-critical facilities and oil and gas and other fields and industry, the role of HVAC plays a decisive role. Background Heating, ventilation and air conditioning are due to the discovery and discovery of many scientists, including Michael Faraday, Willis Carrier, James Joule, William Rankine and Nicolas Carnot people. Some of the world's companies and inventors continue to introduce new and efficient new methods around the industrial revolution. The three main functions of HVAC are heating, ventilation and air conditioning are interrelated and are intended to be provided and properly provided at reasonable installation, operation and maintenance costs. HVAC systems provide ventilation, reduce, maintain the pressure relationship between indoor and outdoor or different living room, air flow into or out of the room characteristics called. In modern buildings, the above functions (including their control systems, and system design and installation) will be integrated in one or more HVAC systems. For small buildings, contractors will directly choose HVAC systems and equipment. If the large-scale construction, by the architect and mechanical, structural and other engineers to analyze, design and identify HVAC system, and then by a professional mechanical contractor to install. HVAC system is an international industry, its related work includes the operation of the system, maintenance, design and architecture, equipment manufacturers and business, research and education promotion. HVAC industry has been managed by HVAC equipment manufacturers, and now there are many international management and standardization organizations concerned about this area, including ,,,, unified Uniform Mechanical Code (Uniform Mechanical Code), to provide HVAC Industry-related services and enhance their standards. Heating and heating systems have appeared in the Roman Empire era, when the public bath in the walls and floors, there is a called the hypocaust duct system. There are many kinds of heating systems. In the cold climate, often use the central heating system to provide private residential and public building heating. The system will include a boiler or a heating furnace for heating steam, water or air, which is normally placed in the building. The use of water as a heat exchange medium is called. The heating system also includes pipes or pipelines that convey the heating fluid, and a radiator that conveys heat to the air by convection. Radiator will usually be buried in the wall or buried below the floor. Most of the heating systems have pumps that allow the system to circulate water, making the heat provided by each radiator not too much.