A degassing module for removal of air and other gases during operation of a medical therapy device that delivers any one of hemodialysis, hemodiafiltration and hemofiltration. The degassing module has a flow-through first chamber that has a hydrophobic vent membrane that has an exterior and interior side forming a portion of the flow-through chamber. The hydrophobic vent membrane is positioned at a higher elevation on the flow-through chamber than a fluid outlet. Fluid flows through the flow-through chamber in a downward direction relative to the hydrophobic vent membrane. A flow-through chamber has a cross sectional area configured to provide for a downward flow velocity of the fluid to be less than the upward rise velocity of a smallest bubble to be removed from the fluid.