Pressurized Water System Tubing & Fittings

Essential Components for Marine and RV Fresh Water Systems

Pressurized water system tubing and fittings form the backbone of onboard fresh water delivery in boats, RVs, campers, and mobile equipment. Unlike traditional home plumbing, these systems must withstand constant vibration, temperature extremes, tight installation spaces, and the unique demands of pressurized portable water delivery. Whether you're replacing worn components, upgrading to modern quick-connect technology, or building out a new water system, choosing the right tubing and fittings ensures leak-free performance and long-term reliability.

How Pressurized Water Systems Work

In marine and RV applications, an onboard pump pressurizes the water system, typically operating between 40-60 PSI. This pressure pushes water from holding tanks through distribution lines to faucets, showers, and other fixtures. The tubing must be semi-rigid enough to maintain its shape and routing, yet flexible enough to navigate tight bends around cabinetry and through bulkheads. Fittings connect these lines at junctions, transitions, and fixture connections. Modern quick-connect fittings have revolutionized these systems by eliminating the need for clamps, barbs, and tools, while providing superior leak resistance and easier serviceability.

Key Considerations When Selecting Components

Material selection matters significantly in pressurized water systems. Quality fittings use FDA-compliant materials certified to NSF-61 standards for potable water contact. Tubing is typically semi-rigid polyethylene or similar food-grade plastic that resists algae growth and maintains flexibility across temperature ranges from below freezing to 150°F for hot water lines. Diameter is equally important—common sizes include 1/2-inch and 3/8-inch CTS (copper tube size), with proper sizing ensuring adequate flow rates without pressure loss. Installation convenience has become a priority, with push-to-connect and quick-connect designs allowing secure connections without specialized tools or thread sealants.

Top Brands in Pressurized Water System Components

The marine and RV industries have established leaders in water system technology. Whale Water Systems pioneered the Quick Connect plumbing system featuring their unique Double Gripper design and cage collet technology that prevents leaks even under excessive pressure or near tight bends. Sea Tech, now marketed as AquaLock by Watts, remains the number one choice for boat builders and RV manufacturers worldwide, offering push-to-connect fittings in both imperial and metric formats with no-tools-required installation. Camco provides dependable water system solutions as part of their comprehensive RV parts lineup, serving the recreational vehicle market with replacement components and upgrade options.

Installation and Maintenance Best Practices

Proper installation begins with clean, square cuts on tubing—any burrs or angled cuts can compromise seal integrity. Tubing should be supported at regular intervals, typically every 36 inches, to prevent excessive load on fittings from the weight of water-filled lines. When routing lines, avoid areas with sharp edges or excessive heat, and use different colored tubing (red for hot, blue for cold) to simplify future service work. Most quality quick-connect systems feature collets with internal O-rings that create watertight seals rated well beyond typical system pressure. Regular inspection of visible fittings and monitoring for pressure drops can catch small leaks before they become major problems, especially important in marine environments where freshwater capacity is limited.