A solenoid valve has a housing which comprises a first and a second housing part, wherein a flexible diaphragm is arranged between the first and the second housing part. A movably mounted actuating element is provided which is connected to the diaphragm and detaches the diaphragm from a valve seat in an operating position of the first and the second housing part upon movement into an open position, and which presses the diaphragm onto the valve seat upon movement into a closed position. The first and the second housing part can take up a service position in which the diaphragm is accessible. The diaphragm is connected with a positive fit to the actuating element in a nondestructively detachable manner such that in the service position, the diaphragm can be removed from the actuating element by releasing the positive fit and can be connected thereto by establishing a positive fit. An assembly and a method of replacing a diaphragm are furthermore proposed.