Energy Efficiency & Air Conditioners

Size

• Buying the correct size air conditioner for the room or area you wish to cool is essential for energy efficiency. Larger air conditioning units use more power than smaller units because they cycle on and off more frequently. A small unit running for long periods is more energy efficient. Select the correct size of air conditioner by allowing 20 Btu of power per square foot of the room or area that you need to cool.

Ratings

• The energy efficiency of air conditioners is measured on the EER, energy efficiency ratio, scale. To meet national appliance standards, room air conditioners sold in the United States must have an EER rating between 8.0 and 9.8. A higher rating indicates greater energy efficiency and the U.S. Department of Energy recommends units with an EER of 10.0 or above.

Installation

• Install the air conditioner carefully to maximize energy efficiency. Make sure the unit is level to ensure the internal mechanisms and drainage system runs properly. Installing the unit in a shaded area on the east or north side of the property can reduce the heating effect of direct sunlight on the air conditioner's heat exchange unit.

Location

• The location of the air conditioner in the room also has an impact on energy efficiency. Try to install the unit away from other electrical items, such as lamps or television sets. The heat from electrical appliances can trigger the air conditioning unit to switch on unnecessarily and use more power. For long, narrow rooms select an air conditioner with fan controls that can push cool air deeper into the room.

Usage

• Try to reduce the amount of time the air conditioner runs. Set the thermostat a little higher to reduce the difference between outdoor and indoor temperatures. Use a regular interior fan elsewhere in the room to help circulate the cooler, conditioned air. Remember to switch off the air conditioner when the house is empty during work hours or when you go on vacation. Service and maintain air conditioning units at the manufacturer's recommended intervals to ensure efficient operation.