This team is recognized for conducting the first study to authoritatively quantify the energy and monetary impacts of improper installation of heat pumps. The study quantifies the impact of single and multiple faults on heat pump performance. The results of this study provided an authoritative technical base for establishing effective commissioning practices in the field and for promoting them in the marketplace. While the industry generally recognizes that poor installation has an effect on air conditioner and heat pump performance, the impacts of such defects have never been characterized previously.