Systems and methods for pumping a non-biological liquid fluid through a sterilizing filter

A method for controlling non-biological liquid fluid flow through a tubing segment including a sterilizing filter in which a pump draws a non-biological liquid fluid through the tubing segment and the sterilizing filter using negative pressure P comprising the steps of:

• a) operating the pump at an initial commanded fluid flow rate to draw the non-biological liquid fluid through the tubing segment and the sterilizing filter;
• b) measuring on a continuous basis the P in the tubing segment including the sterilizing filter;
• c) determining into which of four zones the measured P in the tubing segment including the sterilizing filter falls, a first zone being where P>X1, a second zone being where X1>P>X2, a third zone where X2>P>X3, and a fourth zone where X3>P;
• d) if P in the tubing segment including the sterilizing filter is in the first zone for greater than a first pre-established time period, then increasing the commanded flow rate of the pump, limited to a specified maximum flow rate, and returning to step b);
• e) if P in the tubing segment including the sterilizing filter is in the second zone, then continuing to operate the pump at the flow rate at which the pump is currently operated and returning to step b);
• f) if P in the tubing segment including the sterilizing filter is in the third zone, for greater than a second pre-established time period, then decreasing the commanded flow rate of the pump and returning to step b);
• and
• g) if P in the tubing segment including the sterilizing filter is in the fourth zone, then commanding the pump to stop, wherein each of X1, X2, and X3 is a negative pressure value.