Turn off the water supply to the house at the main valve, which is usually placed near the water meter that measures the amount of water used at the house. Once this is done, open the valves at all the water lines so excess water will drain from the pipes. Then close them again.
Remove the supply line from the valve that runs to the sink or other water discharge area. For the best replacement connection, cut the old valve from the pipe using a hacksaw at least 1/2 inch away from the valve. Use a file to remove any burrs on the pipe after cutting, and with fine-grit sandpaper buff around the first inch of exposed pipe until it shines.
Slip the compression nut from the new valve onto the piece of pipe so that the threads face the exposed end of the pipe. Slide a compression ring on and hold these in place if they are not tight enough to stay on unaided.
Spread a layer of plumbing joint compound around the end of the pipe and position the new valve assembly at the pipe opening. Pull the compression nut so it meets the valve connection and hand-tighten the two together.
Check the connection of the compression fitting to make sure it is seated properly and is secured evenly to the new valve. Tighten the connection completely using an adjustable wrench. Don't over-tighten because this could damage the pipe and compression fitting.
Attach the supply line to the other end of the new valve, using Teflon tape over the threads to create a good seal between the two. Make sure the new valve is in the closed position.
Turn the water on again at the main, and check the new connections to verify that there are no leaks. Carefully tighten any connections that may be leaking. Slowly open the new valve, and look for leaks on the supply side. Turn the water on at the faucet, and verify smooth flow without leaks.
Things You Will Need
- Fine-grit sandpaper
- Compression nut
- Compression ring
- Plumbing joint compound
- New valve
- Adjustable wrench
- Teflon tape
- Even if the old valve can be removed easily, cutting a fresh piece of pipe improves the likelihood of a good secure connection with the new valve.