Fans cool you, not the room
A fan acts as an inside breeze, or perhaps, more aptly, a personalized breeze.
Fans move air, so they don't actually change the temperature of the environment. For example, if you have a ceiling fan in your living room, the actions of the fan don't make the living room a few degrees cooler.
The air being circulated does not change temperature. Heat exchange has to occur for temperature changes, and fans don't do that.
What fans do is circulate the air around an object. That air may have had a heat exchange. Replacing the heated air with non-heated air, creates a feeling of coolness--sort of like a cool breeze on a hot summer day.
Convection
When your body is hot, your brain sends a signal to get rid of some of the heat. Your blood vessels dilate, which causes more blood to travel through the vessels.
This warmed blood is brought to the surface of the skin to be cooled.
Dilation can be seen when a person is overheated and looks flushed. The flushing is the blood racing to the skin's surface and pooling in an effort to be cooled.
When a fan blows across hot skin, it's pushing off some of that heat. It's like blowing on a hot bite of food.
Evaporation
You sweat for a reason, and that reason is to cool down. Sweat cools by evaporation. As sweat evaporates, it takes heat with it. However, if you are standing in an area with no air circulation, your sweat can cause a cloud of you-humidity.
Evaporation is the process of a liquid becoming a gas---your sweat is being sucked up into the air.
If it doesn't move from your immediate area, that can translate in to humidity, or feeling stuffy and hot.
Fans circulate the air. They blow out the stuffy air, and bring in new air.
Tags: change temperature, living room