Thermal performance of solar water heater hanged on balcony wall with separate pressure bearing

In this paper, an analysis has been conducted on an indirect forced circulation solar water heater which is hanged on the balcony wall with separate pressure bearing, a mathematical model was established for this heater, and experiments and calculations have been carried out to obtain the useful heat, daily average thermal efficiency, transient thermal efficiency, heat loss coefficient of the heater, etc., under clear day conditions in winter in Kunming, China. The results show that the thermal performance of such a solar heater is superior, it meets the requirements of the national standards and the residential water usage, and is suitable for utilization integrated with buildings; Solar radiation is the most profound parameter to dictate the thermal performance of the heater; The insulation performance of the storage tank with separate pressure bearing is superior. Nevertheless, the results also demonstrate that further studies are needed to explore in-depth the temperature stratification in the heat storage tank.