Q. Do window fans help cool a room?

Answer

Since window fans are most efficient at removing warm air from a room they are most useful when the temperature inside the house is higher than the temperature outside. To cool a whole home window fans are positioned in open windows to circulate cool air in and exhaust hot air out. Never use window fans until the temperature outside is lower than the indoors. The outdoor temperature must be lower than the indoor temperature for window fans to be effective at cooling a home. Multiple window fans can be used to create a crosswind which drives hot air out and cool air in.