The HVAC aftermarket represents the market for spare parts, accessories, and components related to HVAC systems. The aftermarket also includes replacement, maintenance, and repair services. In terms of geographic segmentation, the Americas accounts for the highest revenue in the global market. This is because the region has a large HVAC installed base. In addition, there are regulatory reforms in the region that are modulating HVAC maintenance procedures and encouraging consumers to adopt energy-efficient and environment-friendly HVAC parts and components. The maintenance and repair service is in tandem with the demand for HVAC components and parts, as all equipment require continuous maintenance.

工程技术服务行业与固定资产投资规模密切相关。我国固定资产投 资持续快速增长的势头大大促进了工程技术服务行业的发展。全国 固定投资完成额呈现由基数扩大而增速已经逐步下滑的常态，截止 2017 年 10 月投资累计完成额为 517817.98 亿元，同比增长 6.89%。 西部地区固定投资增速高于平均增速。以 2014-2016 年三年的增速 来看，东部、中部、西部的年复合增长率分别为 4.77%、5.20%、10.58%。 截止 2017 年 10 月，东部、中部、西部累计完成固定资产投资额 218371.40、131460.22、138028.36 亿元。