The Research Of Applying Heat Pump In The Hot-water Supply System

With the increasing seriousness of the problem of energy and environment more and more HVAC systems have been in service in World, which have significant influence upon energy and environment. Energy saving has become a vital problem. Increasing hot water need causes a rise in the energy consumption. It need a future discuss in this area. Implying heat pump into hot water system in place of traditional heating ways will do goods both in economy and environment.The author mentions the wading pool heat pump, using the fire fight pond. Based on lumped heat capacity method and finite difference method, thermal storage of the wading pool is processed unsteady state heat transferring count through the program. In the continuous andintermittent run of the system, the paper analyses how the pool temperature change. And it also presents the influence of several parameters on heat transfer between the wading pool and the soil. It is feasible that it can be primary heating source in the small-scale buildings and equipment assisting the air source heat pumps in the large-scale buildings.Nowadays, researches of heat pump hot water systems concentrate in the heat pumps only, few take consider of the system as a whole. The paper surveys a heat pump hot water system that is running in a hotel in Changsha, Hunan province.After analyzing 3 ways of hot water supply systems using heat pumps as direct heating, indirect heating and mixing heating, propose 3 ways of laying out water tank in mixing heating system, which is traditional way, storing& heating way and developed of the later one. In the same condition, power consumption of storing& heating way and its developed way is more or less the same, while the traditional way uses up the most of all. Then we analyze the relationships between performance coefficients of heat pump and performance coefficients of hot water system. When choosing proper inlet& outlet temperature range of cooling water in order to improve COP of heat pump system, we should pay attention to optimizing design of water tank and also reducing numbers and energy consumption of heat pumps in the purpose of improving COP of hot water system. Then discuss other ways of energy saving.