How To Eliminate A Leak Within A Compression Fitting On A Copper Water Line

Construction & Contractors Articles

If you have a leak in a connection between a copper water line and a sink, dishwasher or icemaker, then chances are likely that it is a failed compression fitting causing the trouble. While tightening other types of fittings can often resolve a leak, continuing to tighten a compression fitting is useless and may even make the leak worse. Compression fittings can be repaired, but it requires that you disassemble the fitting and replace a key component.

How compression fittings work

Compression fittings include three necessary components: body, nut and sleeve. The body is the largest of these, and it serves as the housing for joining two pieces of tubing or where tubing joins valves, adapters or other fittings. The nut pulls the tubing end toward the body and holds it in place. But it's the most critical component, the sleeve, that ties everything together.

The sleeve in a compression fitting expands and seals the gap between the tubing and body. When you turn the nut with a wrench, it provides the necessary squeezing force that forces the sleeve to push outward and form a watertight fit. However, the sleeve is limited in its ability to expand; if a fitting is disturbed, then the fully-expanded sleeve will slip and cause a leak. Additional tightening does nothing to help and indicates that the sleeve should be replaced. Fortunately, you can replace this item yourself by following the simple procedure below:

How to repair a compression fitting - tools and materials needed

  • Replacement sleeve
  • Tubing cutter
  • Tubing reamer or utility knife
  • Brass wire brush
  • Two adjustable wrenches
  • General purpose light oil

How to repair a compression fitting - step-by-step procedure

1. Turn off the water supply - if your kitchen contains a local water valve, turn it off before proceeding further; if not, turn off the main water valve for your home. Open a faucet or two to release any accumulated water or pressure.

2. Remove the nut from the compression fitting - while holding one adjustable wrench firmly in position on the body of the compression fitting, use the second adjustable wrench to loosen the nut. After the nut is loose, slide it several inches down the copper tubing to keep the nut secure and prevent it from falling off the tubing.

3. Remove the tubing from the body of the fitting - carefully grasp and pull the tubing from the body of the fitting; don't apply too much pressure or you may break or bend the copper line. As you remove the tubing, slide the sleeve from the tubing and set it aside.

4. Inspect and clean the tubing and compression fitting components - once the fitting is disassembled, take a close look at the end of the tubing that you just removed. The end should be perfectly round and in clean, intact condition. If you see any signs of cracking or tearing in the copper, or if the shape of the opening isn't round, then you will need to remove a small portion of the tubing with your tubing cutter. Measure about an inch inward and make a fresh cut in the tubing. Remove any burs with a tubing reamer or utility knife.

Also take a moment to inspect the other components; the inside of the fitting body should be clean of debris, and the threads on the body and nut should also be clean and undamaged. Discard the sleeve since it will no longer be of use, and replace any other components that appear to be damaged. Clean dirty tubing and components with a brass wire brush, and rinse them under running tap water.

5. Reattach the fitting - after inspection and cleaning, slide the fitting nut over the tubing first, then slip a new sleeve over the tubing. Place one drop of light machine oil on the sleeve surface and use your fingers to spread it around the circumference of the sleeve; this will lubricate the threads of the nut.

Next, insert the tubing into the fitting body, and push it into the body until it rests firmly against the shoulder. Following that, slide the nut back up the tubing, over the sleeve and onto the fitting body threads. Use your hand to tighten the nut, being careful to avoid cross-threading it.

6. Tighten the fitting with your wrenches - after hand-tightening the nut, restore the water service to the line. It will probably begin to leak and drip, but that is normal at this point in the repair. Next, position your wrenches on the fitting body and fitting nut, and slowly begin to tighten the connection while watching the leak. Continue to slowly tighten the fitting, and immediately stop turning the wrench when the leaking ceases. It is critical not to over-expand the sleeve, so use only enough force to stop the leaking.

For more information, of you don't have time to make the repairs yourself, contact a local company that offers plumbing repairs


13 July 2015

Exploring Contractor's Hand Tools

Welcome to my site, my name is Hugo Ciela. I'd like to talk to you about hand tools used by contractors of all kinds. Although air and power tools frequently make jobs easier, and sometimes even more enjoyable, hand tools have not lost their place in this industry. Many jobs cannot be completed without a hand tool or two due to their versatility and precision. Contractors of all types, ranging from roofers to foundation specialists, keep a plethora of hand tools in their worksite kit. I will discuss the types of hand tools you might see in those kits. I will also explore all of the different ways they can be used. Please stick around to learn more information about contractor's hand tools.