Written Air coolersAdvantagesLow initial investment (costs 10-15 percent as an AC)Runs at 1/5 th power consumption of ACDoesn't have any special insulation requirements in the roomsSimple mechanism. Maintenance is easy and can be done by anyone, Spare parts are easily and cheaply availableCan humidify air in really dry areasCan operate without stabilizersUses no gases or substances that have negative impact on environmentDisadvantagesCan function only in Dry regions where humidity is less. Cannot be used in coastal regions and areas with high pollutionCan become unhygienic very quickly unless maintained properly. Water has to be changed and the water pads have to be cleaned regularlyCannot cool without humidificationUses a fair amount of water to operate rightCannot be precise with temperature that the cooler will cool toAir ConditionerAdvantagesCan work in areas with any humidity levelsWill cool consistently irrespective of temperature outsideWill dehumidify the air and keep humidity at comfortable levelsRelatively QuietCan control temperature of room preciselyMore hygienic air than air coolers as it filters air as it circulates itDoesn't consume ant water

during operationSome refrigerants are not environmentally safe (for example: R22)DisadvantagesExpensive : initial Cost as well a running costs are very highNeeds to be maintained professionally. Maintenance cost is higherHigh power consumptionNeeds special InstallationNeed goof insulation in room to save power and operate efficientlyNeeds clean power to funvtion and hence stavilizer is needed in areas with poor supplyMy opinionIf a cooler works in your area, it is much more environment friendly than ACsACs are preferable for people suffering from Respiratory disordersPlease never use Air coolers in areas with more than 65–70 percent humidity as it can lead to health issuesWritten Both are working on different Air cooler:Air has capacity to hold water, up to a certain level , known as saturation point, in vapour form. Also energy (or heat) is required when water evaporates from liquid state to vapour state, which is termed as latent heat of vaporization. So, if air can host this water to steam transformation, its temperature can be brought down.

How much temperature can be reduced is depending on how much water can be transformed and settled inside. This ability of air  to reduce temperature by absorbing water is changing with the existing level of water vapour inside it. Hence dry air(low humidity) has more ability to absorb water than humid air which is available near coastal area.Air cooler working on above principle consists of a fan which drives area through a wet medium( say a honeycomb type filter, continuously wetted by a water from a tank.)vertical mount window ac unitMaximum cooling possible with this method is limited to the saturation point(100% humidity)When temperature comes down humidity goes up. second hand portable ac unitAir cooler is not comfortable in highly humid area, say places close to sea.air handling unit vs air conditioner

Air conditioner:A straight forward reduction of temperature when it passes through a cooling coil. Cold medium inside the coil is either a refrigerant( say R22 , R410A etc) or a chilled medium( say chilled water from a chiller). This is generally possible through a vapour compression device. A simple air-conditioner consists of a compressor compressing refrigerant gas to high pressure(automatically high temperature) then cooled at high pressure in a condenser coil to liquid state. High pressure liquid is expanded in a expansion device which results in liquid which thirsts to get converted to gaseous state. This is accomplished in the cooling coil, refrigerant absorbs heat from air surrounding the coil, to change itself from liquid to gas.In market, an air conditioner can be window a/c, split unit, central chiller  fan coil unit.When air temperature is reduced below certain temperature, known as dew point, water starts coming out from air. This is known as condensation.Hence this system can reduce water content(or humidity) of air in addition to reducing temperature.

Written There are principal differences between air coolers and air conditioners. Both of these electronic devices are pathologically different. The air cooler essentially functions by blowing air through a curtain of water khus grass and blades, to cool the room. It’s safe to say that an air cooler also known as a swamp cooler, and wet air cooler cools air through the evaporation of water. It uses the evaporating technique in order to produce the cool air. Evaporative cooling implies that the temperature of dry air can be dropped by putting it through transition of liquid water to water vapour. Sometimes, ice is added to the water in the tank to speed up the cooling process. Doing this may increase the humidity in the room as the process ensues a very fine spray of water. But, this is beneficial in dry areas and hence they are termed as desert coolers. Air coolers work on a simple principle, the lower the humidity, higher the drop in temperature will be, so using them will not bring down the temperature drastically in areas of higher humidity.

Similarly, while using air coolers, you must take utmost care to ensure that there is at least a small space for the cool air to escape from the room; or else, the humidity will increase tremendously and might cause respiratory problems, especially among children and elders.pared to coolers, an air conditioner uses refrigerants in order to cool the temperature. ACs can also reduce the humidity of the air in the area. The term air conditioning means altering the properties of air, temperature and humidity, to more favourable conditions.This is possible due to the property of the refrigerant gas which is pumped by the compressor to absorb enormous quantity of heat, expand, and exit to the coils in the outdoor unit and thereafter to the outside air. This cycle gets repeated till the desired temperature is achieved.Updated Air coolers, technically know as Evaporative cooler, use evaporation of water for cooling the air. Air conditioners, on the other hand, use use a working fluid which goes through a thermodynamic cycle to achieve the same.