Kenmore Reverse Osmosis Membrane Part # 3857705 and 42-38577

North Star Water Treatment Systems manufactures professional-grade residential water softeners, filtration systems, reverse osmosis systems, and replacement components designed to improve water quality and protect household plumbing. Known for dependable performance, easy-to-install designs, and systems built for professional installers, North Star products are widely used in homes where reliable water treatment and long-term system operation are important.

North Star systems are designed to address common water quality concerns including hard water, sediment, chlorine, taste and odour, and iron contamination. Their product lineup includes a broad selection of water softeners, whole-house filtration systems, reverse osmosis drinking water systems, and specialty treatment equipment for residential point-of-entry and point-of-use applications.

About North Star Water Softeners, Filtration & Reverse Osmosis Systems

The North Star product range includes high-efficiency residential water softeners such as the NSC and NST series, whole-house filtration solutions including sediment and chlorine reduction systems, chemical-free iron filtration systems, and reverse osmosis drinking water systems with compatible replacement filters and membranes. North Star systems also feature proven technologies such as AutoSense™, reverse flow regeneration, and an exclusive rotary valve designed for long-term serviceability and performance.

North Star incorporates many EcoWater-built components across its line of water treatment systems. This close relationship often creates crossover replacement part compatibility between North Star, EcoWater, Tap Works, and a number of private-label systems sold over the years under brands such as Sears, Kenmore, GE, Whirlpool, Reem, and others. For service professionals and homeowners alike, this provides valuable options when sourcing hard-to-find replacement parts for older water softeners, reverse osmosis systems, and filtration equipment – including legacy systems that continue operating years beyond their expected service life due to their solid construction, dependable design, and the regular maintenance of their owners.

The widely recognized rotary valve, referred to by professional installers as the "World Valve", is one of the key reasons many of these systems share compatible replacement parts. Common service components include bypass valves, cam gears, motors, rotor discs, seal kits, turbine assemblies, venturi kits, brine valve assemblies, wiring harnesses, monitor kits, RO filter sets, membranes, and other parts used to maintain North Star and compatible equipment, including both current systems and older product lines that can often be repaired, upgraded, or retrofitted for continued use.

If you are looking for a specific North Star water softener, reverse osmosis filter set, replacement valve component, or part not listed on this page, please contact us by email or call our office (1-866-489-4004) for assistance. Our team can help identify the correct North Star component or a compatible crossover part for your water treatment system.

Browse our full selection of North Star water softeners, whole-house filtration systems, reverse osmosis filters, and replacement valve components and get dependable water treatment equipment shipped FAST from our Canadian warehouse DIRECTLY to your door. A real Water Guy can help you select the right parts to maintain your North Star water system.