The Energy Policy and Conservation Act, as amended, (EPCA) requires the U.S. Department of Energy (DOE) to conduct a review of its test procedure for each covered class of covered equipment once every seven years to determine if amendments are needed. If DOE determines that amended test procedures would more accurately or fully comply with the requirements under 42 U.S.C. 6314(a)(2) and (3) (related to representativeness during an average use cycle and not being unduly burdensome to conduct), DOE must prescribe amended test procedures for that equipment. Otherwise, DOE must publish a notice regarding its determination that the test procedure does not need to be amended. DOE proposes to amend its test procedures for water-source heat pumps, with the main changes being ones to expand the scope of applicability of the test procedure, reference different industry standards than currently referenced, change to a seasonal cooling efficiency metric, and change the test conditions used for the heating metric. DOE has tentatively determined that the amended test procedure would produce results that are more representative of an average use cycle and more consistent with current industry practice without being unduly burdensome to conduct. Once completed, this rulemaking will fulfill DOE’s statutory obligation to either propose amended test procedures for this equipment or determine that the existing test procedures does not need to be amended.