本文概述了最近采用的ASHRAE标准124《空间供暖/热水器组合额定值的测试方法》，重点介绍了确定组合年效率所用算法的推导。介绍了几种性能参数对用于空间供暖/热水的热水器的综合年效率和年运行成本的单独影响。这些参数包括回收效率、备用损耗和空间加热效率。还讨论了用水、设计供暖要求和区域对空间供暖季节长度的影响。还概述了获得综合年效率所需的实验室测试程序。关键词:空间供暖、热水、组合锅炉、效率、算法、标准、测试、电器、性能、使用成本、热水器、热负荷引用: ASHRAE Trans。1992年，第98卷，第1部分，论文编号AN-92-2-2665-675，图2。，标签。，参考文献6。

An overview of the recently adopted ASHRAE Standard 124,Methods of Testing for Rating Combination Space-Heating/Water-Heating Appliances, is presented, with emphasis on the derivation of the algorithms used in determining a combined annual efficiency. The individual effects of several performance parameters on the combined annual efficiency and annual cost of operation of a water heater used for space heating/water heating are presented. These parameters include the recovery efficiency, standby loss, and space-heating efficiency. The effects of water use, design heating requirements, and regional effects on the length of the space-heating season are also addressed. An overview of the laboratory testing procedures required to obtain the combined annual efficiency is also presented.KEYWORDS: space heating, water heating, combination boilers, efficiency, algorithms, standards, testing, appliances, performance, cost in use, water heaters, heat load