If it helps, this has something to do with the chemistry of life.
heat always goes from the hottest place to the coldest place. when the temperature of the object in the water is hotter than the temperature of the water, it cools the object. when the temperature of the object in the water is cooler than the temperature of the water, it heats the object. this principle is the basis of an heat exchanger. in the chemistry of life i think it has to do with sweating. your body is hot, when you sweat (water), the heat is transferred to the water and the water gets enough energy to evaporate.
