The generation (and recovery) of water, rather than the reduction of CO2, drives the requirements for the integration of a Sabatier CO2 Reduction Subsystem (SCRS) within an Air Revitalization Subsystem (ARS). It is important, therefore, to understand the system level decisions that impact the water production capability of the Sabatier CO2 Reduction Subsystem. This paper defines each of the operational parameters that affect water production and loss and explores the impact they each have on total water recovery. The particular subsystem parameters examined include hydrogen and carbon dioxide flow rates, feed gas composition, subsystem operating pressure, condensing heat exchanger performance, heat sink temperature, and phase separator performance. Each of these has a minor contribution to the amount of water lost from the system, but combined, their effect is substantial.