It is the process of providing thermal comfort and dehumidification of the indoor air, mostly by cooling. In a broader sense, the term is also used for HVAC, heating, cooling and ventilation or disinfection processes to improve the condition of the air. An air conditioner (AC or A/C in North American English, aircon in British and Australian English) is a device, system or mechanism that uses a cycle to extract heat from the environment for comfort, often in buildings and transportation vehicles.
Air conditioning engineers have broadly divided air conditioning applications into “comfort” and “process”.
Comfort Applications aim to provide thermal comfort preferred by people indoors, even if there is a change in outdoor or indoor heat loads.
People sitting in an office are expected to perform at their peak at 22.2 °C. For every 0.61 °C change in room temperature, the performance decreases by approximately 1%. When working standing up, the highest performance is achieved at slightly lower temperatures. The maximum performance of fatter people occurs at a slightly lower temperature. The maximum performance of thinner people occurs at slightly higher temperatures. Although generally accepted, some people think that the productivity of workers does not change with thermal comfort, as explained by the Hawthorne effect.
Air conditioning for comfort makes large buildings suitable. Without air conditioning, buildings would have to be narrower or built with wells so that they could get enough air with natural ventilation. Air-conditioning also allows buildings to be taller because the wind speed increases excessively in very tall buildings, which is unfavorable to natural ventilation. Comfort applications for various building types are quite different and can be categorized as follows;
- Including low-rise, residential buildings, single-storey family houses, duplex houses and small apartments.
- Such as high-rise, residential buildings, high-rise dormitories and apartments.
- Commercial buildings, they are built for commerce, offices, shopping malls, restaurants, etc.
- Institutional buildings, these include hospitals, government buildings and academic buildings.
- Industrial areas; Here, the comfort of the workers is desired.
- In addition to buildings, air conditioning is also used for the comfort of transport vehicles such as vehicles, trains, ships, airplanes and spacecraft.
Process applications aim to provide a suitable environment for a process to be applied without being affected by internal heat, moisture loads and external environmental conditions. Although it is mostly seen as comfort, it is the requirements of the process, not human preferences, that determine the conditions. Process applications include:
Operating rooms in hospitals; here the air is filtered to reduce the risk of infection and humidity is controlled to reduce the patient’s dehydration. While temperatures are generally in the comfort zone, special applications such as open heart surgery require low temperatures (about 18 °C), and others such as neonatal wards need relatively high temperatures (about 28 °C).
Controlled rooms where integrated circuits, drugs are produced, high air cleanliness, temperature and humidity control are necessary for the success of the process.
Where laboratory animals are kept. Since many animals breed in the spring, keeping them all year in places where conditions are like spring can cause them to breed all year.
Aircraft air conditioning. Although conceptually aimed at providing comfort for passengers and cooling equipment, aircraft air conditioning is a specialized process due to the low air pressure outside the aircraft.
Data processing centers
Physical testing centers
Plant growing areas
Chemistry and biology laboratories
Cooking and processing areas
In both comfort and process applications, the goal is not only to control temperature, but also humidity and air quality.