How to Efficiently Connect PEX to Copper? A Comprehensive Guide

Connecting PEX (cross-linked polyethylene) to copper pipes is a common task in plumbing upgrades and repairs. PEX is widely favored for its flexibility, corrosion resistance, and easy installation, while copper pipes remain a staple in many systems due to their durability and high-temperature resistance.
So, how can you safely and efficiently connect PEX to copper pipes? This article explores three main connection methods and recommends IWISS professional tools to help you choose the best PEX-to-Copper solution.

1. Why is PEX-to-Copper Connection Becoming More Popular?

The demand for PEX-to-Copper connections has steadily increased for modern plumbing installations and renovations. Several key factors drive this trend:

1.1 Combining the Advantages of PEX and Copper Pipes

Both PEX and copper have distinct advantages. Many modern plumbing systems integrate the two materials to optimize installation efficiency and performance:

Advantages of PEX:

• Flexibility: Easily navigates around obstacles, reducing the need for fittings and minimizing potential leak points.
• Corrosion Resistance: Unaffected by minerals or chlorine in water, making it ideal for challenging water areas.
• Freeze Resistance: Expands slightly in low temperatures, reducing the risk of pipe bursting.
• Easy Installation: No welding required, simplifying installation and reducing labor costs.

Advantages of Copper

• High-Temperature Resistance: Suitable for hot water lines and boiler systems.
• Durability: It can last over 50 years, making it ideal for long-term installations.
• UV Resistance: Unlike PEX, which degrades under direct sunlight, it is suitable for outdoor installations without additional protection.

Using PEX-to-Copper connections, plumbing systems in hot and cold water distribution, central heating, and solar water heaters can balance cost, durability, and efficiency.

1.2 The Best Solution for Retrofitting Old Plumbing Systems

Many older homes feature complete copper plumbing systems. However, when upgrading or repairing these systems, many homeowners and contractors opt to replace sections with PEX for several reasons:

• Cost Savings: PEX pipes are significantly cheaper than copper, and installation is more affordable.
• More straightforward Repairs and Expansion: PEX can be quickly extended or replaced, whereas copper repairs require welding.
• Leak Prevention: PEX systems use fewer joints than traditional copper soldering, reducing the risk of leaks.

PEX-to-Copper connections allow gradual upgrades rather than requiring a complete overhaul, reducing renovation costs and downtime.

1.3 Flexible Installation Methods for Various Plumbing Needs

Different PEX-to-Copper connection methods (crimping, push-to-connect, expansion) provide flexibility for various installation scenarios:

• Fire-Safe Alternative to Soldering: In confined spaces or wooden structures where open flames aren't an option, Push-to-Connect fittings offer a safer, faster solution.
• Emergency Repairs: Push-to-Connect fittings allow for rapid connection, making them ideal for quick leak repairs.
• Long-Distance Installations: PEX can bend around obstacles, reducing the need for copper elbows and fittings, leading to a more efficient plumbing system.

To accomplish this transition, we can use the following three main methods:

2. Three Primary Ways to Connect PEX and Copper Pipes

2.1 Crimp/Clamp Connection – Cost-Effective and Durable for Most PEX-B/C Systems

Crimp (copper rings) and Clamp (stainless steel cinch rings) are classic PEX connection methods. This approach requires a copper-to-PEX transition fitting, which is then secured using a crimp or cinch tool to ensure a watertight seal.

Recommended Tools

• CRP1096 – Compatible with 3/8" - 1" PEX clamps, featuring an integrated removal function, perfect for DIY and professional use.

• IWS-1234N – Designed for 1/2" and 3/4" copper rings, featuring convertible jaws for versatile PEX crimping, meeting ASTM 1807 standard.

Pros

• Affordable and cost-effective
• Strong and durable connection for long-term plumbing systems

Cons

• Installation requires a crimping or clamping tool
• Connections are not reusable and must be cut for disassembly

2.2 Push-to-Connect – The Fastest and Easiest Option for DIY Installations

Push-to-Connect fittings (like SharkBite-style designs) allow PEX and copper pipes to be directly inserted into the fitting, enabling quick installation without tools. These fittings can also be removed and reused easily.

How to Remove Push-to-Connect Fittings?

While installation is simple, removal requires specialized tools. IWISS offers three different removal tools tailored to various working conditions:

Recommended Tools

• CRQ01 – Compact but requires more effort, suitable for 1/2", 3/4", and 1" push-fit fittings.
• CRQ02 – Larger but labor-saving, making it ideal for standard push-to-connect fittings.
• CRQ04 – An upgraded version of CRQ02, specifically designed for tight spaces and corner installations.

Pros

• No specialized tools are required for installation, and setup is fast and easy
• Removable and reusable, making it ideal for emergency repairs

Cons

• It's more expensive than Crimp/Clamp connections
• It may have minor leaks over time, especially in high-pressure or high-temperature conditions

2.3 Expansion Connection – The Most Secure Seal for PEX-A Systems

PEX-A (such as Uponor systems) can be expanded using an expansion tool to temporarily enlarge the pipe, allowing a copper transition fitting to be inserted. The pipe then contracts, forming a tight, secure seal.

Recommended Tool

• IWS-1960DT – Designed for 1/2", 3/4", and 1" PEX-A pipe expansion, featuring automatic rotating heads

Pros

• No metal rings, allowing greater water flow
• It is highly durable and provides a superior leak-free seal

Cons

• It only works with PEX-A and is not compatible with PEX-B or PEX-C
• Requires an expansion tool, making installation slightly more complex

3. Choosing the Best PEX-to-Copper Connection Method

4. Conclusion: Selecting the Right PEX-to-Copper Solution

For affordability and durability - Choose Crimp/Clamp
For quick, tool-free installation - Choose Push-to-Connect
For the most secure, high-flow connection - Choose Expansion

Visit the IWISS website to find the best PEX-to-Copper solutions!