A fan by itself cannot cool below ambient temperature, if anything, it heats up the air due to electrical resistance of the fan motor.
Evaporative coolers take advantage of the fact that water absorbs heat in order to evaporate. So basically they operate like humidifiers and introduce humidity in the airflow of the fan. The water absorbs the heat, causing the airflow from the unit to be more cool than the intake air. This only works in very dry climates. If the ambient humidity is high, it will not work.
It’s not the fans that cool the water, rather it’s the water that cools the air. This is why it cools off outside after it rains. It’s not just because of the cloud cover blocking the sun, it’s also because the rain begins to evaporate and takes heat with it.
Latest Answers