Device and method for air-free filling of a fluid management system

A fluid management system having

• a machine-internal fluid line, which is configured to be connected to a fluid input for supply with a flushing liquid, and a fluid output for discharging the flushing liquid,
• a locking device in the fluid line, which divides the fluid line into a first and a second fluid line portion,
• a first fluid conveying means in the first fluid line portion in response to operation of the first fluid conveying means arranged upstream of the locking device,
• a second fluid conveying means in the fluid line portion in response to operation of the second fluid conveying means arranged downstream from the locking device and
• a control device for controlling the locking device, the first fluid conveying means, and the second fluid conveying means,
• wherein the control device is configured to control the first fluid conveying means for conveying liquid in the direction of the locking device in order to increase a pressure in the first fluid line portion relative to a pressure in the second fluid line portion, and which is configured to control the second fluid conveying means for conveying liquid away from the locking device in order to lower a pressure in a second one of the fluid line portion relative to the pressure in the first fluid line portion downstream from the locking device, and
• wherein the control device is configured to open the locking means at least once in the case of increased pressure in the first liquid portion and in the case of lowered pressure in the second liquid portion.