air cooler

accomplished in the cooling coil, refrigerant absorbs heat from air surrounding the coil, to change itself from liquid to gas.

High pressure liquid is expanded in a expansion device which results in liquid which thirsts to get converted to gaseous state.

A simple air-conditioner consists of a compressor compressing refrigerant gas to high pressure

This is generally possible through a vapour compression device.

Cold medium inside the coil is either a refrigerant( say R22 , R410A etc) or a chilled medium

When temperature comes down humidity goes up. Air cooler is not comfortable in highly humid area, say places close to sea.

Maximum cooling possible with this method is limited to the saturation point(100% humidity)

Air cooler working on above principle consists of a fan which drives area through a wet medium

Hence dry air(low humidity) has more ability to absorb water than humid air which is available near coastal area.

This ability of air to reduce temperature by absorbing water is changing with the existing level of water vapour inside it.

How much temperature can be reduced is depending on how much water can be transformed and settled inside.

if air can host this water to steam transformation, its temperature can be brought down.