Room Air Conditioners and Energy Efficiency

In our previous posting we discussed proper cooling capacity when purchasing an AHAM Verifide room air conditioner. After determining the size unit needed, consider its operating efficiency. An efficient room air conditioner uses less electricity so it costs less to operate. To measure efficiency, engineers have established a room air conditioner Energy Efficiency Ratio (EER). It is computed by dividing Btu/h (cooling output) by the watts of power (electrical input) in accordance with Department of Energy Test Procedures. Federal Trade Commission regulations require that this value be placed on the label attached to the product. Thus a 12,000 Btu/h model might use 1,900 watts and have an EER of 6.3 while another model of the same capacity might use 1,350 watts and have an EER of 8.8. The higher EER is the more efficient of the two. The AHAM Verifide directory of room air conditioners lists EERs for all certified units.