Air Conditioning – Important conditions 1
Air improvements for each hour (ACH)
The quantity of periods for each hour that the quantity of a unique space or developing is equipped or eradicated from that house by mechanical and purely natural air flow.
Air handler, or air handling unit (AHU)
Central unit consisting of a blower, heating and cooling components, filter racks or chamber, dampers, humidifier, and other central products in direct get hold of with the airflow. This does not incorporate the ductwork by means of the developing.
British thermal unit (BTU)
Any of quite a few units of electricity (warmth) in the HVAC sector, every single a little additional than 1 kJ. One particular BTU is the electricity necessary to raise just one pound of drinking water just one diploma Fahrenheit, but the a lot of air conditioning distinct varieties of BTU are based mostly on distinct interpretations of this “definition”. In the United States the energy of HVAC devices (the level of cooling and dehumidifying or heating) is in some cases expressed in BTU/hour in its place of watts.
A machine that gets rid of warmth from a liquid via a vapor-compression or absorption refrigeration cycle. This cooled liquid flows by means of pipes in a developing and passes by means of coils in air handlers, fan-coil air conditioning units, or other devices, cooling and usually dehumidifying the air in the developing. Chillers are of two varieties air-cooled or drinking water-cooled. Air-cooled chillers are usually outside and consist of condenser coils cooled by fan-driven air. H2o-cooled chillers are usually within a developing, and warmth from these chillers is carried by recirculating drinking water to outdoor cooling towers.
Gear that performs warmth transfer when mounted within an Air Managing unit or ductwork. It is heated or cooled by electrical indicates or by circulating liquid or steam within just it. Air flowing throughout it is heated or cooled.
A component in the standard refrigeration cycle that ejects or gets rid of warmth from the technique. The condenser is the warm facet of an air conditioner or warmth pump. Condensers are warmth exchangers, and can transfer air conditioning warmth to air or to an intermediate fluid (these kinds of as drinking water or an aqueous option of ethylene glycol) to have warmth to a distant sink, these kinds of as ground (earth sink), a entire body of drinking water, or air (as with cooling towers).
Constant air quantity (CAV)
A technique created to supply a frequent air quantity for each unit time. This phrase is utilized to HVAC devices that have variable offer-air temperature but frequent air movement rates. Most household forced-air devices are tiny CAV devices with on/off handle.
A machine that controls the operation of portion or all of a technique. It may perhaps only turn a machine on and off, or it may perhaps additional subtly modulate burners, compressors, pumps, valves, enthusiasts, dampers, and the like. Most controllers are automated but have user enter these kinds of as temperature established factors, e.g. a thermostat. Controls may perhaps be analog, or digital, or pneumatic, or a mix of these.