An expansion and isolation valve, specifically an electric expansion and isolation valve for operation with the coolant R744, featuring a valve body arranged in a valve body chamber, a seal seat, and a seal, which are arranged along an axial movement direction of the valve body in the expansion valve. The expansion valve is further designed such that in a closed state of the expansion valve, there is a pressure bypass to the valve body chamber, and preferentially, that a valve body diameter at the positions of the seal seat and the seal corresponds with the respective seal diameters.