How to Fix a Broken Copper Line for Mini Split: A Comprehensive Guide

Fixing a broken copper line in a mini split air conditioning system can be a daunting task, but with the right tools and knowledge, it’s a manageable DIY project. This comprehensive guide will walk you through the step-by-step process of repairing a damaged copper line, ensuring your mini split system is back in working order.

Assess the Damage

The first step in fixing a broken copper line is to thoroughly inspect the damage. Carefully examine the copper tubing to determine the extent of the issue. If the damage is a minor kink or bend that doesn’t completely obstruct the refrigerant flow, you may be able to leave it as is. However, if the damage is more significant, such as a complete break or severe deformation, you’ll need to replace the affected section.

Gather the Necessary Tools

how to fix a broken copper line for mini splitImage source: Flickr

To successfully repair a broken copper line, you’ll need the following tools:

  • Pipe cutter
  • Flaring tool
  • Flux
  • Solder
  • Propane torch
  • New copper tubing (1/4 inch or 5/16 inch diameter)
  • Vacuum pump (optional)
  • Refrigerant gauges (optional)

Ensure that you have all the necessary tools and materials before starting the repair process.

Cut Out the Damaged Section

Using the pipe cutter, carefully cut out the damaged section of the copper line. Make sure the cuts are clean and perpendicular to the tube, as this will ensure a proper fit for the new copper tubing.

Flare the Ends

With the damaged section removed, it’s time to prepare the ends of the copper tubing for the new connection. Use the flaring tool to create a flare on the ends of the copper tubing. This flare will provide a larger surface area for the solder to bond to, resulting in a stronger and more secure connection.

Attach the New Copper Tubing

Apply a thin layer of flux to the flared ends of the copper tubing and the corresponding ends of the mini split line set. Using the propane torch, heat the joints until the solder melts and flows, creating a tight seal. Ensure that the connection is secure and there are no visible leaks.

Evacuate and Recharge the System

Once the new copper tubing is in place, it’s essential to evacuate the system to remove any moisture or air that may have entered during the repair process. Use a vacuum pump to evacuate the system, and then recharge it with the appropriate refrigerant using the refrigerant gauges. Refer to the manufacturer’s specifications for the correct refrigerant type and pressure.

Quantifiable Details

  • Copper tubing diameter: Typically 1/4 inch or 5/16 inch for mini split systems.
  • Replacement tubing length: Dependent on the extent of the damage.
  • Propane torch temperature: Approximately 2,500 degrees Fahrenheit for optimal soldering.
  • Refrigerant pressure: Between 50 and 150 pounds per square inch (psi), depending on the specific mini split model.

By following these steps and paying attention to the technical details, you can successfully fix a broken copper line in your mini split air conditioning system. Remember to always prioritize safety and refer to manufacturer instructions or consult a professional if you’re unsure about any part of the process.


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