In short, “no”. The truth is that the cooling produced by an evaporative cooling system is due almost totally to the evaporation of water into the air and has very little to do with the actual temperature of the water being evaporated. Hot water, cold water, lukewarm water, simply doesn’t matter. The laws of physics say it takes 8,340 Btu’s to evaporate one gallon of water. So, when we evaporate a gallon of water into the air coming into a poultry house using either pads or fogging nozzl...es, 8,340 Btu’s of energy in the form of heat is removed from the air which results in a decrease in air temperature. How much cooling will the evaporation of one gallon of water produce? It depends on the volume of air the gallon of water is being evaporated into; more air less cooling, less air more cooling. But, for example, if we evaporated one gallon of water into 100,000 cubic feet of air each minute, we would reduce the temperature of the air by approximately five degrees.