商业建筑及其暖通空调系统由专业的建筑师和工程师团队设计。设计工程师需要精确的设计工具，这些工具需要精确的算法来建模和预测HVAC系统的能源使用和电力需求。设计师必须对工具和算法有信心，尤其是在涉及到更高资本成本、节能系统时。一旦对此类节能系统的预期性能有信心，设计师就更有可能在客户项目中指定这些暖通空调系统。在RP-620项目开始时，发布了模拟水循环热泵和热回收/双循环的计算机程序和算法的验证结果- 捆绑式制冷机性能不可用。如果没有验证，这些系统的预测能源使用和需求的准确性将无法得到保证，结果将包含大量不确定性。

Commercial buildings and their HVAC systems are designed by a professional team of architects and engineers. The design engineers need accurate design tools which require accurate algorithms to model and predict the HVAC system energy use and electrical demand. The designer must have confidence in the tools and algorithms, particularly when it comes to higher capital cost, energy-efficient systems. Once confident of the predicted performance of such energy-efficient systems, the designer is more likely to specify these HVAC systems in client projects.At the outset of project RP-620, published validation results for computer programs and algorithms to simulate water-loop heat pump and heat recovery/double-bundle chiller performance were not available. Without validation, the accuracy of the predicted energy use and demand of these systems could not be assured and the results would contain substantial uncertainties.