Abstract: An ink delivery system having at least one off-axis ink supply container and an on-axis printhead assembly. The printhead assembly includes at least one reservoir and a corresponding standpipe separated by a particle filter. At least one tube connects the off-axis ink supply container to the printhead assembly. A first valve is configured to selectively open a flow path between the tube and the reservoir. A second valve is configured to selectively open a flow path between the standpipe and the tube. A method for controlling effects of accumulated air in a printhead assembly. The printhead assembly has at least one ink reservoir and one standpipe separated by a particle filter. The printhead assembly is fluidicly connected to at least one off-axis ink supply container by at least one tube. The method includes drawing air from said printhead assembly through said standpipe into the tube.

Abstract: A re-circulating fluid delivery system includes an air-fluid separator structure, a fluid plenum in fluid communication with the separator structure, and a free fluid reservoir. A fluid re-circulation path fluidically couples the separator structure, the fluid plenum and the free fluid reservoir. A pump structure re-circulates fluid through the re-circulation path during a pump mode, wherein air bubbles may be separated from re-circulated fluid.