When should you change your ceiling fan direction?
Every 6 months (twice a year).
Best months: April and October (Northern Hemisphere)
How to do it
Flip the switch on the fan housing: counterclockwise in summer to push air down, clockwise on low in winter so the updraft pushes warm air from the ceiling back into the room.
Why it matters
It makes a room feel a few degrees cooler or warmer for almost nothing.
Recommended interval: every 6 months, per ENERGY STAR (U.S. EPA).
General guidance for a typical home; the manufacturer's instructions come first.