If you’re experiencing a plumbing issue, such as a leaky faucet or a running toilet, it’s important to know how to turn off the water supply under the sink. This will help you to prevent further water damage and give you time to call a plumber. Turning off the water under the sink is a relatively simple task that can be completed in a few minutes. However, it’s important to follow the steps carefully to avoid causing any damage to your plumbing system.
The first step is to locate the water shut-off valves. These valves are usually located under the sink, near the base of the faucet. There will be two valves, one for the hot water and one for the cold water. Turn the valves clockwise to shut off the water supply. If the valves are difficult to turn, you can use a wrench to assist you. Once the valves are closed, the water supply to the sink will be turned off.
If you’re unable to locate the water shut-off valves under the sink, you may need to turn off the water supply to your entire home. To do this, locate the main water shut-off valve, which is usually located near the street or in the basement. Turn the valve clockwise to shut off the water supply to your home. Once the water supply is turned off, you will need to contact a plumber to fix the leak or other plumbing issue.
Identifying the Shut-Off Valves
Shut-off valves are essential plumbing components that allow you to control the flow of water to different fixtures and appliances in your home. When you need to turn off the water under a sink, it’s crucial to locate and operate the correct shut-off valves.
Typically, there are two types of shut-off valves located under a sink:
| Valve Type | Function |
|---|---|
| Cold Water Shut-Off Valve | Controls the flow of cold water to the sink. It’s usually located on the left-hand side of the sink cabinet, connected to the cold water supply pipe. |
| Hot Water Shut-Off Valve | Controls the flow of hot water to the sink. It’s typically located on the right-hand side of the sink cabinet, connected to the hot water supply pipe. |
To identify the shut-off valves, start by looking for a small knob or lever on the pipes under the sink. The knobs or levers are usually made of plastic or metal and have a handle that you can turn. If you have difficulty locating the valves, you can consult the user manual for your sink or contact a licensed plumber for assistance.
Locating the Water Supply Line
Identifying the water supply line beneath your sink is the initial step in effectively turning off the water supply. Follow these comprehensive instructions to locate the line:
1. **Inspect your sink’s base:** Examine the area underneath the sink for any pipes or hoses connected to the faucets or appliances. The water supply line is typically made of copper, PEX, or CPVC and may be concealed behind a cabinet panel or sink skirt.
2. **Follow the pipes:** Trace the pipes from the faucets or appliances towards the wall. The water supply line will likely run from the wall or floor towards the fixture. It may have a shut-off valve attached, which is used to control the water flow to the fixture.
3. **Check behind the sink:** If you cannot locate the water supply line from the front, check behind the sink. Access this area by opening the cabinet doors beneath the sink and removing any obstructions. You should be able to see the water supply line connecting to the faucets or appliances from this vantage point.
4. **Identify the main water shut-off valve:** In addition to the individual shut-off valves for each fixture, there may also be a main water shut-off valve for the entire house. This valve is usually located near the water meter or outside the house where the water line enters the property.
Turning Off the Hot Water Valve
Locate the hot water valve, which is typically red or has a red handle. It will be located under the sink, either directly behind the hot water faucet or to the side of it. If your sink has two handles, the one on the left is usually for hot water.
For compression valves:
| Step | Description |
|---|---|
| 1 | Turn the valve handle clockwise until it is snug. |
| 2 | Use a wrench or pliers to gently tighten the packing nut (the ring around the base of the valve handle) just enough to stop the leak. |
For cartridge valves:
| Step | Description |
|---|---|
| 1 | Pull the handle up to release it from the cartridge. |
| 2 | Use a wrench to unscrew the cartridge counterclockwise. |
| 3 | Insert a new cartridge into the valve body and tighten it clockwise. |
| 4 | Push the handle back onto the cartridge and turn it on to check for leaks. |
Turning Off the Cold Water Valve
Before attempting any repairs or changes under the sink, it is essential to turn off the water supply. Here’s a step-by-step guide on how to turn off the cold water valve:
Identify the Main Water Valve
Locate the main water valve, usually found in a utility room or basement. This valve controls the water supply to the entire house.
Turn the Valve Clockwise
Using a pair of pliers or an adjustable wrench, turn the valve clockwise. The valve is closed when it is turned perpendicular to the pipe leading to the sink.
Troubleshooting Tips
- Valve is difficult to turn: Apply penetrating oil to the valve threads and allow it to sit for several minutes before trying again.
- Valve is leaking: Replace the valve washer or packing. Contact a plumber if the leak persists.
- Valve cannot be closed completely: The valve seat may be worn out. Contact a plumber to replace the valve.
Tightening the Valves
1. Locate the valves: Under the sink, find the two valves that supply hot and cold water to the faucet. They’re typically located near the base of the faucet, with handles or levers on top that you can turn.
2. Turn off the water supply: Rotate the handles or levers clockwise to turn off the water flow. You may need to use pliers or a wrench for stubborn valves.
3. Determine valve type: Most valves are either stem-type or compression-type. Stem-type valves have a protruding spindle, while compression-type valves have a nut that you can tighten.
4. Tightening stem-type valves: Using a flathead screwdriver or a wrench, gently tighten the screw located on top of the valve stem. Avoid overtightening as it can damage the valve.
5. Tightening compression-type valves: This involves two methods depending on the valve design:
| Method 1 | Method 2 |
|---|---|
|
Use pliers to tighten the packing nut located below the valve handle. Tighten it gradually while holding the handle securely to prevent it from moving. |
Remove the valve handle and use a wrench to tighten the nut located at the base of the valve stem. Be cautious not to overtighten to avoid damage. |
Inspecting for Leaks
Thoroughly inspecting your under-sink plumbing for leaks is a crucial step before attempting any repairs. Here’s a detailed guide to identify leaks effectively:
1. Visual Inspection
Examine all visible pipes, joints, and fixtures for signs of dripping or moisture. Pay close attention to connections where pipes change direction or transition to different materials.
2. Check Tightness
Hand-tighten any loose nuts or fittings using a wrench or pliers. If tightening doesn’t stop the leak, it may require further repairs.
3. Use a Leak Detector
Electronic leak detectors can pinpoint hidden leaks by detecting water droplets or changes in moisture levels. Follow the manufacturer’s instructions for accurate results.
4. Inspect Supply Lines
Check the flexible supply lines that connect your sink to the water supply. Look for any kinks, cracks, or signs of wear.
5. Test the Faucets
Run water through both hot and cold faucets and check for any unusual noises or leaks. If you hear a hissing sound, it could indicate a washer or O-ring problem.
6. Inspect the Drain
The drain is often overlooked, but it can also be a source of leaks. Inspect the drain stopper for any cracks or debris that may cause water to seep out. Additionally, check the drain pipe for any loose connections or damage.
| Sign of a Leak | Possible Cause |
|---|---|
| Dripping water | Loose connection, worn washer, or cracked pipe |
| Moisture around pipes | Leaking joint, rusted pipe, or faulty fixture |
| Hissing sound when running water | Damaged O-ring or washer |
Using a Basin Wrench for Tight Spaces
A basin wrench is a specialized tool designed for accessing and turning off water supply lines in tight spaces. It features a long, thin handle with a jaw that fits around the hexagonal nut that connects the water supply line to the faucet. Here’s a step-by-step guide on how to use a basin wrench in tight spaces:
- Locate the Water Supply Lines: Identify and locate the hot and cold water supply lines under the sink.
- Choose the Correct Wrench Size: Select a basin wrench with a jaw that fits snugly around the hexagonal nut on the water supply line.
- Align the Wrench: Position the jaw of the wrench over the hexagonal nut, ensuring the jaws are fully engaged.
- Apply Pressure: With one hand, hold the handle of the wrench and apply firm pressure to secure the wrench in place.
- Turn Off the Water Supply: Slowly turn the handle of the wrench counterclockwise to tighten the hexagonal nut and shut off the water supply.
- Check for Leaks: Once the water supply is turned off, inspect the connection point for any leaks or drips.
- Tighten Fully: If necessary, continue tightening the hexagonal nut until it is sufficiently snug to prevent leaks, but avoid overtightening to prevent damage to the water supply lines.
| Advantages of Using a Basin Wrench | Disadvantages of Using a Basin Wrench |
|---|---|
|
|
Avoiding Overtightening
When tightening the packing nut, it’s crucial to avoid overtightening. Overtightening can damage the nut, the valve stem, and the sink itself. To prevent this, follow these steps:
- Tighten the nut until it’s snug.
- Use a wrench or pliers to turn the nut a quarter turn further.
- Stop tightening and check for leaks.
- If there’s still a leak, repeat steps 1-3.
- Once the leak has stopped, tighten the nut a little bit more until it’s secure.
- Do not overtighten!
If you’re not sure how tight to tighten the nut, it’s always better to err on the side of caution and tighten it less rather than more. You can always go back and tighten it more if necessary.
Here’s a table summarizing the steps for avoiding overtightening:
| Step | Action |
|---|---|
| 1 | Tighten the nut until it’s snug. |
| 2 | Use a wrench or pliers to turn the nut a quarter turn further. |
| 3 | Stop tightening and check for leaks. |
| 4 | If there’s still a leak, repeat steps 1-3. |
| 5 | Once the leak has stopped, tighten the nut a little bit more until it’s secure. |
| 6 | Do not overtighten! |
Restoring Water Flow
Once the water supply has been turned off, you can proceed with repairs or other tasks that require no water flow. When you are ready to restore water flow, follow these steps:
1. Locate the water supply valves under the sink and turn them clockwise to open them fully.
2. Open the faucet to allow air to escape from the pipes.
3. Check for leaks around the valves and faucet connections.
4. If any leaks are found, tighten the connections or call a plumber for assistance.
5. Once the water flow is restored, check all connections to ensure they are secure.
6. Run the water for a few minutes to flush out any debris or air pockets from the pipes.
7. Inspect the water pressure. If the pressure is low, there may be a problem with the water supply or the faucet aerator.
8. If the water flow is still not restored, check the water meter to ensure that the water supply is turned on.
9. If the water meter is not registering any water usage, you may have a problem with the water meter itself or the main water supply to your home. In this case, contact your local water utility company for assistance.
Locate the Shut-off Valves
Find the shut-off valves under the sink. There are usually two valves, one for hot water and one for cold water. The valves are typically located near the base of the faucet, directly below the sink. They are usually made of metal or plastic and have a handle or knob on top.
Turn Off the Valves
Turn the shut-off valves clockwise to close them. You may need to use pliers or a wrench to turn the valves if they are difficult to turn by hand. Be sure to close both the hot and cold water valves.
Check for Leaks
Turn on the faucet to make sure the water is completely off. If there is still water flowing, the valves may not be closed properly or there may be a leak in the pipes. Tighten the valves or call a plumber to fix the leak.
Troubleshooting Common Issues
Leaking Shut-off Valves
If the shut-off valves are leaking, you may need to replace them. To do this, turn off the water supply to the sink and disconnect the old valves. Wrap the threads of the new valves with Teflon tape and screw them into place. Turn on the water supply and check for leaks.
Corroded Shut-off Valves
If the shut-off valves are corroded, you may need to replace them. To do this, turn off the water supply to the sink and disconnect the old valves. Use a hacksaw to cut the old valves off at the base. Clean the area where the new valves will be installed and solder the new valves in place. Turn on the water supply and check for leaks.
Frozen Shut-off Valves
If the shut-off valves are frozen, you can try to thaw them out using a hair dryer or a space heater. Be careful not to overheat the valves, as this could damage them. Once the valves are thawed, turn on the water supply and check for leaks.
How to Turn Water Off Under Sink
If you need to turn off the water under your sink, there are a few simple steps you can follow:
-
Locate the water shut-off valves. These are usually located under the sink, behind the hot and cold water pipes.
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Turn off the water supply to the sink by turning the valves clockwise until they are hand-tight.
-
Check to make sure the water is off by turning on the faucet. If water comes out, then the valves are not closed all the way.
People Also Ask
How can I tell if my water shut-off valves are working properly?
To test your water shut-off valves, turn off the water supply to the sink and then turn on the faucet. If water comes out, then the valves are not working properly and need to be replaced.
What should I do if I cannot turn off the water supply to my sink?
If you cannot turn off the water supply to your sink, you may need to call a plumber. There may be a problem with the valves or the pipes.
