Humidifiers, by definition, are devices for adding moisture to the air. Thus, to humidify is to increase the density of water vapor within a given space or room. Air humidification is affected by vaporization of water and always requires heat for its proper functioning. Thus, devices that function to add moisture to the air are termed humidifiers, whereas devices that function to remove moisture from the air are termed dehumidifiers.
Humidifiers
As previously noted, air humidification consists of adding moisture. Following are the types of humidifiers used in air-conditioning systems:
? Spray-type air washers
? Pan evaporative humidifiers
? Electrically operated humidifiers
? Air-operated humidifiers
