Air Washers: A New Look at a Vintage Technology

Last year marked the 100th anniversary of the first modern day air-conditioning system designed by Willis Carrier. 1 It consisted of a cooling coil arrangement in which supply air was cooled and dehumidified by indirect heat exchange with cold water pumped through tubing. Carrier surmised that an alternative design using direct contact between the air and chilled water might improve performance. In his early air-conditioning systems, he observed that, although the air came in contact with water on the cooling coil surface, dehumidification occurred.