Because the water pump absorbs water and forms a vacuum by the suction pipe, the water is pressed into the suction pipe of the water pump by atmospheric pressure, and the atmospheric pressure is constant. The height of the water pump water pipe is too large. If the pressure range of the atmospheric pressure is exceeded, the water cannot be sucked. . An atmospheric pressure is a little more than 10 meters of water (10.33 meters). In theory, as long as it does not exceed this height, in fact, due to the influence of altitude, resistance and other factors, the actual installation height of the water pump suction pipe is lower than this figure. About 7-8 meters. High Performance Garden Light,High Lumen Led Street Light,Outdoor Led Street Light,Solar Powered Integrated Street Lamp Jiangsu chuanglv Transportation Facilities Co., Ltd , https://www.clsolarlights.com