Patent ID: 8490422

Claim:
An air cooler for cooling and humidifying outdoor air with two stages of cooling and humidification comprising: a first stage for cooling and humidification with constant wet bulb temperature, the air cooler having a first stage pump connected to a first stage tank circulating water over the first stage evaporative cooling media cooling and humidifying the air passing through following a constant adiabatic wet bulb temperature line, the condition of leaving air depending on media thickness and efficiency; said first stage tank being supplied with water from external source; a second stage for cooling with humidification, said second stage including an insulated tank or non-insulated tank embedded inside the first stage tank or in separated tanks, said tanks being connected by distribution chambers or other means so water is free to move between said tanks; said second stage tank being served by an independent second pump circulating water on a second row of evaporative cooling media, make-up water for said tank supplied directly from water leaving first stage media which is equal or lower than outdoor air wet bulb temperature; said temperature of air leaving the second stage evaporative media following the line toward the second stage tank water temperature, cooling humidifying air to a stable wet bulb and dry bulb temperatures.