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The Cool Choice for Room AC

When the weather warms up, get the best room or window air conditioner by choosing one that has earned the ENERGY STAR. Get tips on how to choose the right size room air conditioner for your window- or through the wall-unit, and learn how to make sure it is properly installed to save the most energy and keep you cool.


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The Cool Choice for Room AC. When the weather warms up, make the cool choice of a new ENERGY STAR® certified room air conditioner.

Size your AC for Comfort and Savings. Bigger is not always better! An oversized unit will cool the room, but only remove some of the humidity. This will leave the room with a damp, clammy feeling. A properly sized unit will deliver maximum comfort and savings. Use this chart as your guide.

  • If the room is heavily shaded, reduce capacity by 10%.
  • If the room is sunny, increase capacity by 10%
  • If the room is a kitchen, increase capacity by 4000 BTUs.

Proper AC Installation and Use is the Key to Cool. An improperly installed room air conditioner leaks as much air as a 6-square-inch hole, increasing energy costs and making your home less comfortable. Follow these A.C. tips to beat the heat:

  • Be sure to follow the instructions and use the insulation materials included with your room air conditioner.
  • Make sure the unit is level so the drainage system works effectively.
  • Don't put lamps or TVs near the A.C. thermostat as the extra heat will cause it to run longer.
  • Set the thermostat as high as is comfortable, typically 78° F. You'll appreciate the savings.
  • On humid days, set the fan speed low. Slower air movement removes more moisture.
  • Use an extra fan to spread the cooled air around.
  • At the end of the cooling season, if possible, remove the room A.C. unit to minimize heat loss.  Or use an appropriately-sized cover during winter.

An ENERGY STAR certified Room AC is the simple choice to save energy, save money, and protect the climate.

ENERGY STAR room air conditioners use 10 percent less energy, and cost less than $75 per year to run, on average.

ENERGY STAR room air conditioners come with higher quality insulation, improving comfort and savings by creating a better seal with the window opening.

ENERGY STAR room air conditioners that feature smart functionality offer greater control over comfort and energy savings-turn off the unit remotely, schedule temperature settings, and receive updates on energy usage.

If all room air conditioners sold in the U.S. were ENERGY STAR certified, the savings would reach more than $350 million annually, preventing greenhouse gas emissions equivalent to over 570,000 vehicles.

Learn more about the Cool Choice for Room A.C. at

ENERGY STAR is the simple choice for energy efficiency. For more than 20 years, EPA's ENERGY STAR program has been America's resource for saving energy and protecting the environment Join the millions making a difference at