Compression Fittings

Compression fittings are sometimes a Do It Yourselfers best friend. When your in a jamb and can't seem to get a valve soldered out comes my compression valves. 

A compression fitting is used to join two pipes together or a pipe to a valve. A compression fitting has three pieces, a compression nut, a compression ring and the compression seat. First the nut is slid onto the pipe, then the compression ring is slid on. The end of the pipe is slid into the fitting. Slide the nut to the threaded end of the fitting and tighten. As the nut is tightened, the compression ring compresses the pipe in the seat. Amazing no leaks.

Make sure the pipe is pushed all the way into the fitting. This is a common mistake which will result in a leak. 

Be careful when bending the pipe, a compression ring will not slide over a bend in the pipe. If you have to bend the pipe make sure the last few inches remain straight.

Only use a compression fitting when your sure that your fixture will not move. A compression fitting is designed to stop a pipe from pulling out of the seat but it is possible to spin the pipe within the fitting which can result in the loosening of the nut and then you've got a leak. If an existing compression fitting begins to leak you can try loosening the compression nut and then retighten.

You can over tighten a compression fitting so be careful. Tighten the nut to the point that you feel resistance, then a half turn more. Turn on the water and check for leaks. If the fitting does leak turn the water off and tighten another 1/4 turn, test for leaks once again. Do this until the leak stops.

Don’t mix materials, if your connecting plastic tubing don’t use a copper compression ring, make sure you use a plastic compression ring.