The Advantages of Capillary Fittings: A Comprehensive Guide

Capillary fittings, also known as Soldered fittings, are a popular choice in plumbing and heating systems due to their reliable, strong, and leak-proof connections. Used extensively in both residential and commercial applications, these fittings can either be brazed or rely on capillary action to draw solder into the joint, creating a durable bond between pipes.

In this guide, we will explore the key advantages of capillary fittings and why they are a trusted option for professionals and DIY enthusiasts alike.

What Is A Capillary Connection?

A Capillary Connection is a type of joint used in plumbing and heating systems that connects a fitting and a pipe through soldering or brazing.

In both methods, a narrow gap exists between the fitting and the pipe. When heat is applied, the filler metal melts and is drawn into the gap through capillary action, forming a strong bond between the two components.

Brazed joints are stronger than soldered ones, as they require higher temperatures and use different filler metals. Soldering utilises solder, while brazing uses a brazing rod, making brazed connections more robust but also more demanding in terms of heat and skill.

Where Are Capillary Fittings Used?

Capillary fittings are used in a wide range of applications across plumbing, heating, and gas systems due to their strong, reliable, and leak-proof connections. Here are some common areas where capillary fittings are used:

They are commonly found in:

• Domestic Plumbing

• Heating Systems

• Gas Installations

• Refrigeration and Air Conditioning

• Industrial Applications

What Types of Capillary Fittings Are there?

End Feed Fittings

End Feed fittings are a type of capillary fitting that uses capillary action to draw solder into the joint between the fitting and the pipe, creating a strong, reliable seal. End Feed fittings are distinct because they require the installer to manually apply solder during installation.

Solder Ring Fittings

Solder Ring fittings come pre-loaded with a ring of solder inside the fitting, making the installation process simpler and more consistent compared to traditional End Feed fittings. When heated with a torch, the pre-installed solder melts and creates the soldered joint. Solder Ring fittings are particularly advantageous for those looking to streamline the installation process while maintaining high-quality results.​

What Are The Advantages Of Capillary Fittings?

Considerations

Safety

The use of an open flame during installation can pose fire risks, especially in confined or flammable areas. Always take appropriate precautions such as ensuring good ventilation, keeping flammable materials clear, and having fire safety equipment nearby.

Use The Correct Solder and Flux

It’s important to choose the correct solder and flux for your specific application. For potable water, use lead-free solder, while specialised solder or brazing may be necessary for other applications.

Importance of a Skilled Installation

A secure and leak-free capillary joint requires good technique. Skilled labour is essential to correctly apply heat, ensuring the solder fully bonds with the fitting and pipe for a reliable connection.

Conclusion

Capillary fittings offer numerous advantages that make them a preferred choice for plumbing and heating installations. Their strong, reliable connections, proven durability, cost-effectiveness, and compact design make them suitable for a wide range of applications. Whether you’re working on a new installation or repairing existing pipework, capillary fittings provide a dependable, professional finish that stands the test of time.