A device having a flow channel for a fluid has a nonreturn valve arranged in the flow channel, the nonreturn valve allowing the fluid to flow through the flow channel in a first direction and preventing it from flowing through the flow channel in a direction counter to the first direction. The device furthermore has a flow detector for detecting the flow of the fluid through the flow channel, wherein the flow detector detects a change in the nonreturn valve. This detected change serves as an indicator for the flow of the fluid. The device enables simplified flow detection, in that a nonreturn valve that is present is used as an indicator.
