How to Install Compression Fittings on a 1/4 Water Line

Compression fittings allow you to make a plumbing connection without using solder.

Install Compression Fittings on a 1/4 Water Line
A ¼- inch water line supplies the water to appliances such as an icemaker in a refrigerator. A compression fitting generally makes this connection. The compression fitting consists of three parts: the compression nut, ring and seat. Most people can install a compression fitting on a ¼- inch water line with just a few basic tools. .

Slide the compression nut onto the ¼-inch water line. The threads should be facing towards the open end of the line.

Slide the compression ring onto the water line. The water line must protrude at least 1/8 of an inch beyond the compression fitting. You must use a plastic compression fitting if you are using a plastic water line. Check with your local hardware store to ensure that your fittings are compatable with your water line.

Connect the compression nut to the threaded male water intake compression seat. The last couple of inches of the water line must be straight. A bend can result in a water leak. Turn the compression nut by hand clockwise on the threaded water intake tube. Tighten the compression nut with a wrench. Do not over tighten the nut.

Turn the water valve on. Check for leaks.

Things You Will Need

  • ¼ inch plastic or copper water line
  • Compression nut
  • Compression ring
  • Compression seat
  • Wrench set


  • Make sure that the water line extends far enough beyond the compression ring to extend into the water intake.
  • Leave extra length on the water line to allow for movement of the appliance. If the water line is too short you can spring a leak when you move the appliance.


  • Watch for leaks. Compression fittings can develop very slow water leaks.