Valve and method for using the same

The invention embodiment provides a valve, which comprises a valve body, a valve core, a first sealing element and at least a second sealing element; wherein, a cavity and a plurality of fluid passages are arranged in the valve body, and each fluid passage comprises a first fluid port and a second fluid port; the first fluid port is communicated with the cavity and the second fluid passage is usedto communicate with an external device. The valve core can rotate inside the cavity; and the first sealing element seals the cavity from the outside ambient. The second sealing element divides the space between the valve body and valve core into a plurality of sectors, each of which is corresponding to at least one first fluid port, so as to guide the liquid in the corresponding external device into the sector; thus, the pressure difference of the liquid at both sides of the second sealing element is less than the fluid pressure at least at one side.