A method of priming an infusion system, comprising: providing a system having an infusion chamber provided with an infusion liquid, the infusion chamber connected to an infusion conduit having a first valve, the system having a cross conduit intersecting the infusion conduit at a location between the infusion chamber and the first valve, the cross conduit coupled to an aspiration chamber, the cross conduit having a second valve, the aspiration chamber coupled to a vacuum source; filling the infusion conduit with a first volume of the infusion liquid, the infusion conduit having an infusion port exposed to a non-liquid environment having a first pressure, wherein the non-liquid is any gas or gaseous mixture; closing the first and second valves to isolate the infusion chamber; operating the vacuum source to create a second pressure in the aspiration chamber that is lower than the first pressure; opening the first valve and the second valve to produce a second volume of the infusion liquid in the infusion conduit to flow over the first valve towards the infusion chamber, wherein opening the first valve and the second valve to produce the second volume of the infusion liquid in the infusion conduit to flow over the first valve comprises: opening the second valve to create the second pressure in the infusion chamber; closing the second valve to isolate the infusion chamber at the second pressure; and after opening and closing the second valve, opening the first valve to allow the second volume of the infusion liquid to flow over the first valve; wherein the second volume of the infusion liquid is less than or equal to the first volume of the infusion liquid. providing a system having an infusion chamber provided with an infusion liquid, the infusion chamber connected to an infusion conduit having a first valve, the system having a cross conduit intersecting the infusion conduit at a location between the infusion chamber and the first valve, the cross conduit coupled to an aspiration chamber, the cross conduit having a second valve, the aspiration chamber coupled to a vacuum source; filling the infusion conduit with a first volume of the infusion liquid, the infusion conduit having an infusion port exposed to a non-liquid environment having a first pressure, wherein the non-liquid is any gas or gaseous mixture; closing the first and second valves to isolate the infusion chamber; operating the vacuum source to create a second pressure in the aspiration chamber that is lower than the first pressure; opening the first valve and the second valve to produce a second volume of the infusion liquid in the infusion conduit to flow over the first valve towards the infusion chamber, wherein opening the first valve and the second valve to produce the second volume of the infusion liquid in the infusion conduit to flow over the first valve comprises: opening the second valve to create the second pressure in the infusion chamber; closing the second valve to isolate the infusion chamber at the second pressure; and after opening and closing the second valve, opening the first valve to allow the second volume of the infusion liquid to flow over the first valve; opening the second valve to create the second pressure in the infusion chamber; closing the second valve to isolate the infusion chamber at the second pressure; and after opening and closing the second valve, opening the first valve to allow the second volume of the infusion liquid to flow over the first valve; wherein the second volume of the infusion liquid is less than or equal to the first volume of the infusion liquid.