WEH series evaporation wet film humidification is an isoenthalpy method. Evaporation of water is induced by absorption of energy from the ambient. The dry-ball temperature in the air drops while the absolute humidity increases, but the total enthalpy in the air is held constant. Wet film humidifier has low cost, clean, and will not cause condensation. Water is circulated and evenly distributed to the wet curtain. Hot and dry air is blown in by a working fan to the wet curtain, then cool and wet air is blown out.