Evaporative coolers cool the air using a simple natural process: the evaporating water decreases the temperature of the air. A pump takes the water from a tank and dampens a large pad made of natural cellulose. A powerful ventilator aspires air through the filter. The water evaporates from the filter and decreases the temperature of the air by several degrees. The fresh and clean air flows into the room and cools it down.
The Elite and Master range of evaporative coolers range from 45 to 200 litre capacities and with air displacement from 4000m3 per hour to 30,000m3 per hour the area which you are looking to cool will determine which cooler you require.