For years I assumed the little switch on the side of my ceiling fan was broken, because flipping it never seemed to do anything I could feel. Turns out it was working perfectly, and I just had no idea what it was for.

That switch reverses the fan, and using it twice a year makes your house more comfortable for free.

Summer: counterclockwise

In warm weather the fan should spin counterclockwise. That pushes air straight down and creates the wind-chill effect that makes a room feel cooler. Stand under it and you should feel a breeze.

• Counterclockwise pulls air up and pushes it down onto you
• Use the highest speed you can stand

This is the setting most fans are already on, which is why most people never think about the switch. It is the winter setting that gets forgotten.

Winter: clockwise

When the heat is on, flip the switch so the fan spins clockwise on low speed. This does the opposite: it gently pulls cool air up from the floor and pushes the warm air that has risen to the ceiling back down the walls.

• Clockwise redistributes warm air without creating a draft
• Keep it on the lowest speed so you do not feel the breeze

It feels like nothing, which is exactly the point. The warm air that used to sit wasted up near the ceiling gets mixed back into the room, so your heater does not run as long.