Keeping Your Home Cool in the Summer Heat Using a Window A/C

Selecting A/C Unit Size

• The size of the room that needs to be cooled will determine the size of the A/C unit necessary for the task. Measure the room or area to be cooled and multiply the length by the width in order to arrive at the square footage. All air conditioner units have BTU or British thermal unit cooling capacity rates, so if the area to be cooled is 100 to 150 square feet, look for a 5,000 BTU size A/C. "Reduce the BTU capacity by 10%" if the room is heavily shaded, or "if the room is very sunny, increase the BTU capacity by 10%," according to the Consumer Energy Center.

Home Electrical System Capacity

• One important factor to after is whether your room or even house or apartment has the electrical capacity to meet the unit's requirements. For instance, most room units operate on either 115-volts or 230-volt circuits. If your home or apartment is standard, then the electrical receptacle connection is for a 115-circuit. Yet, if you are trying to cool a large room in your home with a large window AC 230-volt unit, the room may need a dedicated electrical circuit to accommodate the larger unit, according to the U.S. Department of Energy.

Buy Energy Efficient Window Air Conditioners

• When you are thinking cool, also think green by purchasing an energy efficient unit. A room air conditioner's efficiency is measured by the energy efficiency ratio (EER.) The higher the EER ratio your intended A/C unit is, the more efficiently the air conditioner will perform. The goal is to buy an air conditioner that is an Energy Star-qualified model, because those units have higher EERs. Look for units with an EER of 10.0 or above.

Selecting Air Conditioner Features

• When buying a room air conditioning unit consider that the unit's features are nearly as important as the ability of the air conditioner to cool your room. One feature is very useful is a remote control to adjust the air conditioner's settings. Also, look at models that have touchpad controls, built-in timers as well as louvers that will adjust the direction of the airflow automatically. A few other useful features to consider are a dehumidifying mode and fresh-air intake or exhaust settings.