Consistent with the requirements under the Energy Policy and Conservation Act (EPCA), as amended, the U.S. Department of Energy (DOE) is examining whether to amend the current energy conservation standards for single package vertical air conditioners (SPVACs) and single package vertical heat pumps (SPVHPs), collectively referred to as single package vertical units (SPVUs), found at 10 CFR 431.97. EPCA requires the Secretary to determine whether updating the statutory energy conservation standards is technologically feasible and economically justified, and would result in significant additional energy savings. In this rulemaking, DOE proposes to amend the current energy conservation standards for SPVUs such that the existing standard levels would be based on a new cooling efficiency metric of Integrated Energy Efficiency Ratio for SPVACs and SPVHPs, and the current heating efficiency metric of Coefficient of Performance for SPVHPs (but without any increase in stringency). In addition, DOE has initially determined that more-stringent standards for SPVUs would not be economically justified and would not result in a significant conservation of energy. Once completed, this rulemaking will fulfill DOE’s statutory obligation to either propose amended standards for this equipment or determine that the existing standards do not need to be amended.