Main Water Valve Is Leaking – What to Do

When a water leak occurs, it is important to access the main water valve to shut off the water supply. However, the main water valve itself may leak. Slow water leaks from a main water valve could be a sign of a plumbing issue and should be resolved right away.


What is the main water valve?

main water valveThe main water valve supplies water to the entire house. When the pipe is open, water flows through it. During a water damage emergency, it becomes necessary to immediately turn off the main water valve and thereby disrupt the flow of water supplying the leak.

A home may feature a main water valve consisting of one of two designs: a gate valve or ball valve. A gate valve has the potential to leak, corrode, and become otherwise damaged. Although gate valves can last for years, they can become stuck when not turned for prolonged periods.

Homeowners are advised to turn the gate valve periodically to ensure it will function in the event of an emergency. Opening the valve should be done gently and without excessive force. Turn the handle counter-clockwise and without jerking the handle.

The typical gate valve requires rotating the handle six times before it fully opens. Once resistance is felt, stop turning the handle. Continuing to turn the handle despite resistance will cause damage and is likely to result in a main water valve leak.

Closing the gate valve requires equal care. Avoid applying excessive pressure or force when closing, as such actions have the potential to bend the gate or seal and result in permanent damage. The stem of the gate valve may even snap when the handle is jerked.

A full-flow ball valve is commonly found in homes with plastic or copper main water pipes. Turning off the ball valve is quicker with a simple one-quarter turn of the metal handle. The ball valve contains a ball that either allows or blocks the flow of water through it.


What To Do if the Main Water Valve is Leaking

main water valve leakWhen the main water valve leaks, homeowners can resort to the following DIY options. If the property is built with a gate valve, it is prudent to upgrade to a ball valve. Plumbing professionals recommend ball valves, since they are less likely to leak and endure longer than gate valves.


DIY Option 1: Tighten the Packing Nut

A main water valve may start to leak around the gate valve stem after opening and closing the valve. A water leak at the valve stem suggests that the valve is not fully turned off. The packing nut ensures a watertight seal where the valve stem and water line meet.

Since the packing nut holds the stem of the gate valve in place, gently tightening this nut will stop the leak. However, it is critical to not overtighten the nut. Overtightening the nut can create a situation in which it will be difficult to turn the valve again.

Using a wrench, turn the packing nut a quarter inch. Examine the valve for leaks. If the valve continues to leak, slightly tighten the packing nut a second time. Should the gate valve still leak after another inspection, it is necessary to try a different method to stop the leak.


DIY Option 2: Replace Packing Material

Replacing the packing material under the nut can fix the main water valve leak. Packing material hardens or disintegrates over time, creating a solid seal; this can cause eventual leaks in the valve. Before replacing the material, ask the utility company to shut off the water from the street.

Empty all the remaining water from the home’s water line by opening a faucet. Loosen the shutoff valve handle and the packing nut. Remove the old packing. Wrap replacement packing material (available at hardware stores) three times counterclockwise around the stem.

Next, screw the packing nut in place. Ensure that the new packing material is snug around the packing nut. Be careful to avoid overtightening the packing nut. Once the packing catches and fits snugly, turn on the water. Re-examine the valve for any leaks.


DIY Option 3: Replace the Washer

Replacing the washer may be necessary if the main water valve continues to leak. The packing washer itself may be the culprit, especially if it is faulty. First remove the valve handle. Using a wrench, dislodge the packing nut. Remove the existing washer and replace it with a new one.

It is important to purchase a new washer in the exact size as the previous one. Ensure the size match by removing the old washer and comparing it with the ones available in the hardware store. Once the washer is successfully replaced, check the valve again for leaks.


What To Do if the Leak Causes Water Damage

water damage restoration servicemasterA main water valve can leak and cause tremendous water damage to the property. While water valve leaks are one source of unwanted moisture inside the home, several other scenarios, from storms to burst pipes, can produce equally disastrous results.

When you are confronted with a messy case of water damage, consult the water damage restoration pros at ServiceMaster DAK. Our crews of IICRC certified water damage cleanup technicians will return your water damaged property to its pre-loss condition fast.

Water damage of any extent is an emergency situation. Porous structural materials, like wood and drywall, absorb moisture and allow it to spread rapidly. ServiceMaster DAK water damage cleanup specialists utilize powerful water extraction and dehumidification equipment to dry the property.

Air movers are set up and monitored daily. Speedy drying is critical to preventing the development of mold and mildew infestations in the water damaged areas. Our skilled technicians also take daily moisture and humidity readings to ensure that the home or business meets the dry standard.

Whether the water damage to your home or business is caused by natural or manmade events, ServiceMaster DAK will fully restore your property. Water damage happens unexpectedly, which is why we respond to emergencies 365 days a year. Call for quality water mitigation in the areas surrounding Northbrook, Illinois.



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