Most people think of ceiling fans as a warm weather appliance – you use your ceiling fan in the summer to cool off then turn it off when the temperatures get cool. But ceiling fans can also be used to help warm the rooms in your house during cold weather.
The key to a ceiling fan's effect lies in the direction the fan's blades turn. Usually, a ceiling fan's blades are set to turn in the direction that will force air down into a room – most often, counter-clockwise, though it depends on the slope of the fan's blades. As the air blows over the people in the room, it cools them off. The actual temperature in the room does not get lower, but the wind chill created by the fan makes the people in the room feel cooler.
But when cooler weather arrives, you can use your ceiling fan to help warm a room by reversing the direction that the blades turn. If you reverse the direction, instead of pushing air down over the people in the room, creating wind chill, the blades will push the warmer air trapped between the fan and the ceiling up against the ceiling. The ceiling will then deflect the warm air down into the room, where people can feel it. If you leave the fan low low, the people in the room will not feel a wind chill, but the warm air will be forced down into the room, making it more comfortable.
Many fans have a simple switch for reversing direction, but if you can not find a toggle switch on your fan, consult the manufacturer for instructions.