Principle of water compressor: water compressor, the air inside the compressed air bag is pressed out by the piston, thus forming the pressure difference. The pressure is out of balance due to the strong and small impact of pressure. At the same time, the fluid, acting on gravity, flows from a high pressure area to a low pressure area and the faucet flows to the external container. To be able to push a liquid from a low point to a high point without consuming electrical energy.