To fix a dripping/leaking shut off valve, use an adjustable wrench to tighten the packing nut which will compress the washer and stop the leak. If that does not work, loosen the packing nut and wrap Teflon packing around the valve’s bonnet threads. Tighten the packing nut and check if the leak stops.
Fixing a leaking shut-off valve is essential to prevent water damage and maintain the integrity of your plumbing system. Here’s a brief summary of how to address this issue:
Here is a brief a summary of how to fix a leaking shut off valve:
- Turn Off Water Supply: Locate the main water supply valve to your home and shut it off to stop the flow of water. This valve is typically located near the water meter or where the water line enters your house.
- Relieve Pressure: Open a faucet downstream from the leaking shut-off valve to release any remaining water pressure in the line. This will help prevent a sudden gush of water when you disassemble the valve.
- Inspect the Valve: Carefully examine the shut-off valve to identify the source of the leak. Common areas where leaks occur include around the valve stem and the connection points.
- Tighten Connections: If the leak is at the compression nut or threaded connections, try tightening it using a wrench. Be cautious not to overtighten, as this can damage the valve or pipe.
- Replace Packing Nut: If the leak is coming from the valve stem, you may need to replace the packing nut. First, loosen the packing nut with a wrench and remove the valve handle. Replace the packing material (usually a graphite or Teflon packing) and reassemble the valve.
- Replace the Valve: If tightening or repacking the valve doesn’t resolve the leak, you may need to replace the shut-off valve. To do this, you’ll need to cut the pipe on both sides of the old valve and install a new valve using compression fittings or soldering (for copper pipes).
- Apply Thread Sealant: When installing a new valve or making connections, use thread sealant (Teflon tape or pipe dope) on the threads to ensure a watertight seal.
- Test for Leaks: After making any repairs or replacements, turn the main water supply back on and carefully inspect the repaired area for leaks. If you detect any leaks, shut off the water supply and recheck and tighten the connections.
- Restore Water Pressure: Once you are confident that the leak is fixed, open the downstream faucet to release any air from the pipes and restore water pressure.
Shut off valves cost between $10 and $30. A plumber will however charge you between $150 and $200 to replace the valve for you depending on your location and the scope of work.
How to Fix a Leaking Shut Off Valve
There are 3 methods you can use to fix a leaking/dripping shut off valve. I will start with the easiest and fastest of them all and then we will look at the others in order of ease of repair.
You will need the following items for this job:
- Adjustable wrench
- Teflon packing (optional)
- Shut off valve washer (optional)
- Screwdriver (optional)
The following are the 3 ways to fix a dripping shut off valve:
1. Tighten the Packing Nut
This is the best method to fix a leaking shut off valve without turning off the water.
A dripping shut off valve can be easily fixed by just tightening the packing/bonnet nut. This is the nut that is just below/next to the valve’s handle/knob.
Grab an adjustable wrench or slip-joint pliers and gently tighten the valve’s packing nut. Since the nut will not be very loose, this will involve turning it by about 1/8 or 1/4 of a turn clockwise.
Check if the dripping stops. If indeed the dripping stops then that is the end of the job for you.
2. Wrap Teflon Packing around the Valve Spindle
Teflon packing isn’t the same as Teflon tape, although the later can be used in the absence of the former although not ideal.
If tightening the packing nut does not stop the leak, you will need to wrap Teflon packing around the spindle threads of the valve to help it create a watertight seal. Here is how to go about it:
- Turn off water supply to the dripping valve. You house’s main shut off valve is located in the basement near the water heater or on an external wall where the main water line enters the house. If it is the main shut off valve that is leaking, you will need to turn off water from the water meter shut off valve near the street.
- Drain water from the pipes by turning on a faucet.
- Use a wrench or slip-joint pliers to loosen the packing nut.
- Pull the packing nut all the way back to expose the threads of the valve’s spindle.
- Apply about 3 wraps of Teflon tape on the spindle threads.
- Screw in the packing nut until just hand-tight.
- Gently tighten the packing nut using a wrench or pliers but not crazy tight.
- Turn on water to the valve back on.
- Open the valve slowly and check if the leaking has stopped.
3. Replace the Packing Washer
If you have tried the above 2 methods but still your shut off valve is leaking, the packing washer is completely worn out and replacing it is the only viable solution.
You can buy a packing washer from your nearest plumbing store. You may want to take a picture of the shut off valve so that the store can give you the correct washer. These washers are really cheap and fast to replace compared to replacing the entire valve.
Once you have bought the packing washer, this is how to proceed:
- Turn off water to the valve and open a faucet to drain water from the pipes. I always avoid draining the water heater since an empty tank will cause the element to burn. Unless you turn off the power to the heater prior.
- The valve handle is connected to the valve stem using a screw. Use a screwdriver to remove the screw.
- Once the screw is out pull out the handle.
- Loosen and remove the packing nut using a wrench or slip joint pliers.
- Slide out the old packing washer.
- If the valve stem is corroded, scrub off the corrosions and mineral deposits using an emery cloth.
- Slide in the new washer.
- Screw in the packing nut until just hand-tight then tighten it further with the wrench but do not overtighten it.
- Use the screwdriver to attach the valve handle using the screw.
- Turn on the water supply to the house back on.
- Slowly open the shut off valve and check if the dripping/leaking has stopped.
And basically that is how to fix a dripping/leaking shut off valve.
If everything else fails, you can always replace the shut off valve. Replacing a shut off valve is not an easy task and you will need to hire a licensed plumber, unless you are an experienced DIYer.
Here is a great video on how to replace a leaking shut off valve.