How to Avoid Compression Pipe Fitting Leaks?

In this blog post, you’ll read:Compression fittings can leak due to improper use, faulty installation, high water pressure, or damaged pipes. To fix leaks, shut off the main valve, loosen and retighten the compression nut, and check for any remaining leaks. If necessary, replace the fitting using high-quality materials like brass or stainless steel and apply thread sealant for a tighter seal. Proper installation and maintenance are key to preventing leaks.
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Ever wonder why compression fittings sometimes leak? Well, let’s break it down. Compression fittings contain three key components: a compression seat, a nut, and a ring. But what happens when one of these parts isn’t installed properly or gets damaged? Leaks occur.

In this article, we’ll explore the primary reasons behind compression fitting leaks and how to fix them.

compression pipe fitting
compression pipe fitting

What causes the leaks in pipes? 

Leakages in compression pipe fittings can be due to multiple reasons, including issues with installation, overpressure, or rough usage.

Improper use

  • It would be best if you always used compression fittings on stationary connections. This means pipes linked to compression fittings should not move back and forth.
  • Overtightening the fitting may result in a leakage. We recommend tightening the nut only half a turn beyond where you feel resistance.

Wrong installation 

pipe fitting installation 
pipe fitting installation

Another source of leakage is faulty installation. When installing compression fittings, be careful to push the pipe in. Even if you feel any resistance, don’t stop until it’s completely inserted. If you’re having problems, remove the pipe and label it halfway. You can use this mark to eliminate any uncertainty. Continue pressing until the mark matches the edge of the fitting or a reference point on it. This ensures an airtight seal and prevents leakage.

Most pipe fittings manufacturers provide you with an installation manual. You should read the manual before you install the fitting.

High water pressure 

If the water pressure in your pipes is high, it can also lead to water leakage, especially if the connection or fittings of the pipes are at an angle. High pressure deforms the o-ring, which results in a leakage.

Many pipe fitting manufacturers offer passion compression fittings and high-pressure fittings. These fittings have a more durable o-ring and evenly distribute pressure across the fitting. This makes the high-pressure compression fittings ideal for angle connections.

Pipe damage 

pipe damaged 
pipe damaged

Securing a sealed connection is impossible when the pipe end is scuffed up or uneven. So, you need to ensure the pipe cut is completely straight. We recommend using a pipe cutter rather than a blade or saw for a clean finish.

How do I Fix leaking compression fittings?

The most reliable method to fix a compression fitting leak is loosening and tightening the compression nut. Here’s a detailed method:

  • First, shut off the main valve and make sure the water supply is off.
  • Loosen the compression nut. Use a dry towel and bucket to catch water that might leak while loosening.
  • Now tighten the nut back.
  • Turn the water back on and check for any leaks.

If it still leaks, you may need to replace the fitting.

How do we replace the compression fittings? 

  • Close the inlet valve to turn off the water before replacing the compression fitting.
  • Two pairs of pliers are required to unscrew the compression fitting. Secure the male end of the fitting with one pair of pliers and use the other pair to crank the compression nut counterclockwise to release and remove it.
  • After unscrewing the nut, twist and pull the compression ring off with the pliers.
  • Next, use a file to smooth off the sharp edges on the pipe end. Installing the new nut, ring, and seat onto the pipe end requires removing the old compression nut. After making sure everything is tight, reactivate the water supply.
fix leaking compression fittings
Fix leaking compression fittings.

If you are unable to turn off the water, consider using electrical freezing kits or aerosol sprays to temporarily freeze the pipe before replacing the fitting.

Some Additional Tips 

  • Sometimes, removing the old compression fitting becomes difficult, and you may need to use a hacksaw to physically cut the nut. It would be best to cut as close to the rear as possible.
  • We advise using a plumber’s grease or pipe dope when changing the compression fitting. Teflon tap should not be used since it may cause a loose seal by preventing the fitting from being screwed down all the way.
  • Select sturdy fittings like brass or stainless steel, as they are less likely to corrode and wear out over time. Long-term financial savings can be achieved by making a somewhat higher initial investment in high-quality fixtures.
  • Leak prevention and a tighter seal can be achieved by using thread sealant. Before installing the fitting, select a premium thread sealant appropriate for your plumbing application and lightly apply it to the threads.

Parting Words 

As we conclude our discussion of how to avoid compression pipe fitting leaks, it’s evident that a few easy procedures may go a long way toward a leak-free compression fitting. You can prevent pipe compression fitting leaks by following proper installation methods, regular maintenance, and investing in high-quality fittings.


Can you rely on compression fitting? 

Compression fittings are reliable when installed correctly, but nailing the installation and maintaining maintenance is key to avoiding leaks.

How do you stop a leaking compression fitting?

To stop a leaking compression fitting, properly install the fitting, inspect for damage, avoid over-tightening during installation, and replace it if leaks persist.

How tight do I tighten a compression fitting? 

Typically, after hand tightening, a compression fitting nut requires one full turn.

Can I reuse a compression fitting? 

While compression fittings can often be reused if undamaged and disassembled correctly, it’s best to go for a replacement to guarantee a secure seal.

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