A cleaning catheter (200) includes fluid-delivery and suction lumens (520, 530). A flow regulator (700) defines suction and fluid ports (830, 827). A mechanical user control element (320) is configured to mechanically and non-electrically set activation states of the flow regulator (700), and transition between first and third configurations via a second configuration. When the control element (320) is in the first configuration, the flow regulator (700) blocks fluid communication (a) between the suction port (830) and the suction lumen (530) and (b) between the fluid port (827) and the fluid-delivery lumen (520). When the control element (320) is in the second configuration, the flow regulator effects fluid communication between the suction port (830) and the suction lumen (530), and blocks fluid communication between the fluid port (827) and the fluid-delivery lumen (520). When the control element (320) is in the third configuration, the flow regulator (700) effects fluid communication (a) between the suction port (830) and the suction lumen (530) and (b) between the fluid port (827) and the fluid-delivery lumen (520).
