Kitchen sink trunk valves control the supply of hot and cold water in the sink. Over time, with normal wear and tear, these valves may start to leak. The internal operation of the valve may also fail, making it impossible to close the water supply. If you need to replace the kitchen sink cut-off valves, you will need some basic plumbing tools and the knowledge to do the job.
Locate the main water lock for your home. Turn the main shut-off valve in a clockwise direction to stop the flow of water to all outlets in the house. Open the sink faucet you are working to allow all the excess water in the pipes to drain.
Place a bucket under your shutoff valve to catch and water remaining on the line or accessory. Use your wrench to remove the water supply line that extends from the shut-off valve into the sink.
Use the wrench to remove the old copper valve water supply pipe that extends behind the wall. Turn the nut that connects to the valve counterclockwise (based on the point of view of the pipe and no valve) using your clean rag rub any residue or dirt from the pipe, once the valve has been removed.
Unscrew the nut and ferrule from the water supply end of the new cutting valve. The old nut and ferrule will probably remain stuck in the copper tube due to the tightness of the old connection. Apply pipe joint compound to the valve threads and slide the valve over the copper pipe.
Start by tightening the nut on the valve thread. Use your wrenches to hold the constant valve while tightening the nut on it. Tighten the nut until it is firmly in place.
Use the wrench to reinstall the water supply from the line sink to the other end of the new valve. Tighten firmly to secure a good seal. Open the main water shut-off valve and test the seals.
Tips & Warnings
If you have a leaky valve below your sink, it is possible to fix the leak by tightening the nut just under the handle.
Never force pipe joints or valves. A break in the pipeline could cause severe flooding and damage to your home.
Do not over tighten compression fittings or run the risk of leakage.