The efficiency of room air conditioners is now defined in terms of EER--electrical efficiencyratio. In traditional engineering terms the EER is Btu per watt-hr at the ratingpoint. The rating point established by ASBRAE Standard 16 and the basis for the presentindustry certification program is 80 F D.B. and 67 F W.B. indoors and 95° D.B., 75° W.B.outdoors. EER is the cooling capacity in Btu/hr divided by the watts consumed at thisrating point. According to the certification directory published by the Association ofHome Appliance Manufacturers, 1973 room air conditioners had EER's ranging from below 5to 12.