The invention relates to a valve comprising: at least three channels (2, 9, 11) opening into a common space; a metering gate (12) pivotable in a first channel (2); a diverter gate (10) pivotable between a position for shutting off a second (9) or third (11) channel; and an actuation device (15) for actuating the gates (10, 12), said actuation device (15) comprising an actuation wheel (16) for actuating at least one of the gates and having at least a first configuration in which the metering gate (12) does not shut off the first channel (2) and the diverter gate (10) does not shut off the second (9) or third (11) channel. The actuation device (15) is configured such that, while in the first configuration, the rotation of the actuation wheel (16) causes: the diverter gate (10) to pivot substantially as the diverter gate (12) pivots slightly; and, subsequently, the metering gate (12) to pivot.
