Step 3 · Remove Old Angle Stop
To remove the old angle stop from the copper pipe stub-out, you must use two wrenches. Grip the body of the angle stop valve firmly with one adjustable wrench to hold it stationary. Use a second, larger adjustable wrench to grip the large compression nut at the back of the valve (where it connects to the wall pipe). Turn the second wrench counter-clockwise to loosen the nut. This two-wrench technique is crucial to prevent the copper pipe from twisting inside the wall. Once the nut is loose, you can unscrew it completely and slide the entire valve off the pipe.