An angle valve is commonly referred to as a shutoff valve and may need to be replaced from time to time. However, before you can replace an angle valve, you will need to know the correct size and diameter.
Step 1 - Shut Off the Water
Before you begin, shut off the main water line for your home. You can do this at the main shutoff valve, located at or near your home's water meter.
Step 2 - Remove the Angle Valve
Depending on the type of connection, you'll need to use an adjustable wrench or tubing cutter to remove the faulty valve. In some cases you may even find it easier to use a hack saw to cut the pipe. If using a cutter or saw, try to cut the pipe as close as possible to the valve fitting. If using a wrench, try not to damage the threaded end of the pipe when you remove the valve.
Step 3 - Measure the Pipe
Use a measuring tape to measure the diameter of the pipe where the angle valve was connected. Write this measurement down and take it with you when you go to the hardware store to purchase a replacement.
Step 4 - Take the Valve with You
If you find it hard to accurately measure the diameter of the water pipe, take the faulty angle valve with you to the store. Employees of the plumbing section in the hardware store should be able to help you match up the valve with a new replacement.