As Water is evaporated, energy is lost from the air thus reducing temperature. The standard impeller is aluminium.
Evaporation will take place when the Humidity is below 100% and the air begins to absorb water. Any given volume of air can hold a certain amount of water vapour and the degree of absorption will depend on the amount it is already holding.
Energy is required to change water from liquid to vapour. This energy is obtained in an Adiabatic process from the air itself Air entering SYMBIOSIS Air washer gives up heat energy to evaporate water.