How to Choose the Right Window Air Conditioner

Window air conditioners provide much-needed relief on hot summer days, keeping your home cool and comfortable. But with so many models, sizes, and features available, finding the right unit can feel overwhelming. Choosing the wrong one can lead to wasted energy, higher cooling costs, and a room that still feels warm or stuffy.

Below are a few things to consider when shopping for a new window air conditioner, along with tips to help you operate it efficiently and maintain a comfortable home.

Selecting a Window Air Conditioner

Choose the Proper Size

Choosing the right-sized unit is important for balancing both comfort and energy efficiency. An undersized unit struggles to cool rooms and uses more energy. Meanwhile, an oversized unit may cost more upfront and cool the room too quickly without removing enough humidity, leaving the space feeling damp and uncomfortable.

Cooling capacity is measured in BTUs (British Thermal Units), which is the amount of heat an air conditioner can remove in one hour.

Use this guide from ENERGY STAR to match your room’s square footage to the BTUs you need:

You can then make adjustments based on the following factors: 

• Reduce BTUs by 10% if the room is heavily shaded
• Increase BTUs by 10% for sunny rooms
• Add 600 BTUs per person beyond two occupants
• Add 4,000 BTUs for kitchens

Look for the ENERGY STAR Label

ENERGY STAR-certified room air conditioners can use 20% less energy than standard models. Many also feature advanced technology and operate at lower noise levels. 

Look for Variable Speed Technology

Standard AC units cycle fully on or off, causing temperature swings and higher energy use. Units with variable-speed compressors adjust cooling output continuously, helping to:

• Maintain steady, comfortable temperatures
• Reduce noise
• Use significantly less energy

Consider U-shaped or Saddle Style Window Units

These designs mount within or around the window frame, allowing you to open and close the window even with the unit installed. They also place the compressor outside the room, providing:

• Less indoor noise
• Greater outdoor visibility
• More flexibility in window operation

Explore Smart and Connected Features

Many ENERGY STAR-certified window air conditioners include smart features that allow you to: 

• Turn the AC on or off remotely
• Schedule temperature changes
• Monitor the unit’s energy use

Tips to Maximize Savings

Proper installation and operation of your window air conditioner will make a big difference in its efficiency. Here are some tips to get the most out of your unit: 

• Seal gaps around the unit to prevent air leaks.
• Make sure the unit sits level so it drains properly.
• Keep heat-producing devices (lamps, TVs) away from the thermostat. 
• Set your thermostat to the highest comfortable temperature.
• Run an additional fan in the room to circulate cool air.
• Remove the unit from the window at the end of the cooling season to prevent heat loss. 

Get a $150 Rebate on Window Air Conditioners

Efficiency Smart’s Home Energy Rebates program lets you save even more with a $50 rebate on a qualifying window air conditioner, now increased to $150 through September 30! 

Do you have questions about choosing the right unit or want to explore more ways to save energy? We’re here to help. Contact us at 877-889-3777 or [email protected].