The UPA is being upgraded by NASA to correct design weaknesses and improve maintainability. There are multiple projects within the UPA upgrades effort, and they are in varying stages of completion.

The Distillation Assembly (DA) was updated to improve bearing material, reduce a leak path, and make use of an upgraded toothed gear belt to extend life. The upgraded DA was installed on 9/10/2020 and is operating at 350% of legacy expected lifespan.

The upgrade that is still in work is the development of the Purge Pump and Separator Assembly (PPSA); it is a redesign of both the legacy Pressure Control and Pump Assembly (PCPA) ORU and the Separator and Plumbing Assembly (SPA) ORU, and is intended to be smaller, more efficient, maintainable at a lower level, and potentially more reliable. The initial version of PPSA flew in July 2023 but was removed in Oct due to an inability to reduce pressure. The hardware returned and a failure investigation was performed. Teardown, Test, & Evaluation (TT&E) revealed a design problem with a valve within PPSA. the valve was redesigned and the PPSA is scheduled to fly 2026.

Additional upgrades were developed for ground demonstration (Advanced Recycle Tank Filter Assembly) quantity sensor, Single-Channel Fluids Pump (SCFP), conductivity sensors, etc.

The DA primarily targets reliability with the intent of extending installed life of that ORU (which has been demonstrated for at least the first upgraded unit). This would reduce the number of spares needed for an Exploration mission. The PPSA is intended to decrease the initial system mass/volume as well as that of spares because components can be changed out individually. Single Channel Fluids Pump (SCFP) makes use of a similar concept to reduce initial component mass/volume as well as enabling the replacement of individual components within the system. The SCFP is being tested on the Integrated ECLSS Ground Testbed and has demonstrated the capability to back-flush the UPA, a critical function for future dormancy operations on an Exploration mission.