At What Temperature Should You Set Your Air Conditioner at Night?

Recommended Temp

• You may be the type who likes simple answers, and you just want a number. The official word on where to set your central air conditioning thermostat at night is available from the U.S. Department of Energy. The DOE is always concerned with energy consumption by American families, and they suggest a setting of 78 degrees Fahrenheit whenever cooling is needed while the family is at home. This setting is plenty cool enough, particularly at night when temperatures drop.

Ceiling Fans

• If your home does not have ceiling fans, you may wish to install them in the bedrooms. You can save energy by raising the temperature on your air conditioner at night if you sleep under ceiling fans. While the fans do not actually lower the air temperature in rooms, they create the equivalent of a “wind chill” effect that can make the rooms feel 5 degrees cooler. You can save energy by setting your thermostat to 83 degrees Fahrenheit overnight and running fans to make it feel like it’s still set at 78 Fahrenheit.

Away Overnight

• If you and your family are on vacation or are otherwise planning to be gone overnight, there is no need to keep your air conditioner set as low as it would be if you were home. You may choose not to run the system at all, or if you don’t like coming into a hot house when you return, you may just want to set it a little higher. Before you leave, set the thermostat to 85 degrees Fahrenheit to save money while you are away.

Every Degree Counts

• If you think you can be comfortable if the house is just a bit warmer, experiment with it. When you get your thermostat up above 80 degrees Fahrenheit, you can really start saving money in the long run. Once you are above 80 degrees Fahrenheit, you can save 2 to 3 percent on cooling costs for every degree you raise the temperature on your air conditioner. Keep this in mind when considering if your home is absolutely as warm as it can get to remain comfortable.