摘要:Air source heat pump has the characteristics of high efficiency, energy saving, green and pollution-free, and has been widely used in building energy saving projects. However, the frosting phenomenon of the air source heat pump evaporator during the heating operation in cold areas in winter will reduce the heat production of the system, affect the comfort experience, and even cause the system down or irreversible damage to the heat pump system when the frosting is serious. This paper summarizes the research of domestic and foreign scholars on air source heat pump defrosting, analyzes the existing problems of defrosting technology, and finally looks forward to the future development trend of air source heat pump defrosting research.