In the real world of plumbing, projects are rarely entirely new construction. More often, they involve renovations, repairs, and retrofits where new materials must seamlessly connect to existing systems. A common and critical challenge is integrating modern PEX piping with traditional copper. Historically, this required transition fittings and often still involved soldering. However, with the advent of pipe press fittings technology, this process has been revolutionized. This article explores how Uponor, a leader in PEX systems, provides a streamlined, reliable solution for connecting PEX to copper using their press fitting methodology.
The Challenge of Connecting PEX to Copper
For decades, copper was the plumbing standard. In countless homes and buildings, a robust copper infrastructure is already in place. The goal for many plumbers and homeowners is to integrate the benefits of PEX—flexibility, freeze resistance, and corrosion immunity—into these existing systems. The connection point between the two different materials is a potential vulnerability if not done correctly. Traditional methods like soldered sweat adapters require open flame and significant skill, while mechanical thread adapters can introduce leak points.
The Uponor ProPEX Press Solution
Uponor’s solution leverages the power and simplicity of pipe press fittings. The system utilizes Uponor’s proprietary ProPEX press fittings and a compatible press tool (like those from Viega or Milwaukee) to create a perfect, permanent connection between PEX tubing and copper pipe in seconds.
The key component is a ProPEX Press Transition Fitting. This fitting is engineered with two distinct ends:
- One end is designed to accept PEX tubing. It features the standard ProPEX design with a stainless-steel sleeve and a built-in EPDM O-ring seal.
- The other end is a copper stub-out, which is essentially a short piece of copper pipe that is pre-attached to the fitting body. This copper end is designed to be inserted into a standard copper socket press fitting.
Step-by-Step: How to Connect PEX to Copper with Press Fittings
- Shut Off and Drain: Isolate and drain the section of the existing copper line you will be working on.
- Cut the Copper Pipe: Use a tube cutter to make a clean, square cut on the copper pipe. Deburr the inside and outside of the cut end thoroughly.
- Prepare the PEX: Cut the Uponor PEX-A tubing squarely with a dedicated PEX cutter.
- Select the Fittings: You will need two press fittings:
- A standard copper press fitting (e.g., a coupling).
- An Uponor ProPEX Press Transition Fitting.
- Press the Copper Side: Slide the copper press fitting onto the prepared end of the existing copper pipe. Insert the copper stub-out end of the Uponor transition fitting into the other side of the copper press fitting. Use the press tool to crimp the copper fitting, creating a secure seal between the old copper and the new transition fitting.
- Press the PEX Side: Slide the PEX tubing onto the ProPEX end of the transition fitting until it bottoms out. Use the press tool with the appropriate Uponor ProPEX jaws to crimp the stainless-steel sleeve, creating a permanent seal on the PEX side.
- Inspect and Pressurize: Visually inspect both press connections. The sleeves should be evenly compressed. You can then repressurize the system immediately—no waiting required.
Why This Method is a Game-Changer
- Eliminates Soldering: This is the biggest advantage. There is no need for an open flame, which is a major safety hazard, especially in retrofit and repair situations where walls are open and fire risk is high.
- Incredible Speed: The entire connection process takes less than a minute per joint, dramatically speeding up renovation workflows.
- Superior Reliability: The press connection is machine-made and consistent. It eliminates the human error potential in soldering (e.g., cold joints, burned flux) and provides a leak-proof seal that is often more reliable than a soldered joint.
- Works in Wet Conditions: Unlike soldering, which requires a perfectly dry pipe, press connections can be made on damp pipes, making it ideal for emergency repairs or tight spots where draining water completely is difficult.
Conclusion
The ability to seamlessly connect PEX to copper using pipe press fittings is a testament to how modern technology simplifies and improves upon traditional plumbing techniques. Uponor’s ProPEX Press Transition Fittings provide a safe, fast, and incredibly reliable method for integrating the benefits of PEX into existing copper systems. This approach not only protects the valuable time of plumbing professionals but also ensures that the critical transition between old and new is the strongest part of the system, not the weakest.
Frequently Asked Questions (FAQ)
1. Do I need a special press tool for Uponor ProPEX press fittings?
Yes. You must use a press tool that is compatible with Uponor’s ProPEX press system. The jaw design and pressing profile are specific to Uponor fittings. Many major tool brands, like Viega and Milwaukee, offer compatible jaw sets for their press tools.
2. Can I use this method to connect to any type of copper pipe?
Yes, this method works with Types K, L, and M copper tubing, provided you use a copper press fitting that is sized correctly for your existing copper pipe’s outside diameter.
3. Is the connection made by the press fitting as durable as a soldered joint?
Yes, and often it is considered more reliable. The press connection creates a mechanical grip and a seal that is highly resistant to vibration and thermal cycling. Major manufacturers subject these joints to testing that far exceeds industry standards for soldered joints.
4. What is inside the transition fitting? Is there a seal?
The PEX side of the Uponor ProPEX Press Transition Fitting contains a factory-installed EPDM O-ring, which is responsible for creating the water-tight seal against the PEX tube. The copper-to-copper connection is sealed by the pressed copper fitting itself, which compresses onto the plain metal surfaces.
5. Does this require any special training or certification?
While the process is simpler than soldering, proper training is essential. It is crucial to understand tool operation, fitting recognition, and the importance of proper tube preparation (clean, square cuts, deburring). Many manufacturers and suppliers offer training sessions on proper press technique.
