The invention provides a valve comprising a house and a drum rotatable in the house. The house comprises a plurality of substantial identical tubular mid-section house members, a bottom house member, and a top house member. When connecting the house members to each other, a continuous outer wall surrounding a house cavity, a port, and a plurality of nozzles being in fluid communication with the house cavity is provided. The drum comprises a plurality of substantial identical tubular mid-section drum members, a bottom drum member, and a top drum member. When connecting the drum members to each other, an inner wall having an outer surface being adapted for rotation in contact with a corresponding inner surface of the outer wall, the inner wall comprising a plurality of conduits is provided. During rotation of the drum, the conduits can be brought into and out off fluid communication with the nozzles in order to provide passages between the port and the nozzles. Furthermore, the invention provides a set of members to form a valve, and a system for thermal exchange.