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How To Replace Main Shut-off Valve Without Turning Off Water [Explained]

It’s frustrating when you experience gradual leaks. And, what’s the cause of those? Well, mineral deposits and grits could block off the cutoff valves! 

You have to replace the main valve in your home and another one by the street too.  

How to replace the main shut-off valve without turning off water? 

Replacing the main shut off valve is quite easy and requires three steps only. First, locate the valve, then test the valve. And finally, remove the valve and place a new one. While you replace it, make sure you’re doing it fast. Otherwise, you might lose gallons of water. 

We’ve described the procedure for you A-Z. You’ll understand how it works.

On that note, let’s begin the journey- 

When Do You Need To Change Your Main Shut-off Valve

A water supply line is connected to each faucet and toilet in your home. Each connection to the supply line has its own type of shut off valve. There is also a single main shutoff valve. This allows you to turn off the water in your entire house. 

If your main shutoff valve is leaky, try tightening the valve and see if it stops. If it doesn’t, we need to find another solution. If the main valve at home is dripping, you’ll need to replace the street-side valve as well. 

Is your home old? Then you might have an old main shutoff valve too. Saddle valves might leak because it’s an old fixture. 

How To Replace Your Main Water Shut-off Valve [3-Step Guide]

Now, it’s time to unveil the ways you could use to replace the main water shutoff valves. Let’s break the entire process down for you:

Step 1: Locate The Main Shut-off Valve

It’s a common problem finding the main shutoff valve. As it’s not located somewhere you can easily find it, most people cannot find it. But we’ll guide you through- 

Firstly, look for the main water shutoff valve on the inside of your house. It’ll usually be situated on the home’s perimeter. This is where the water plunges into the house first. Also, this is where the water main generally starts at the street and runs straight to your house. 

If you cannot discover the shutoff valve, you can check the property inspection report. It was probably produced for you during the final stages of your house purchase. 

Look in the report’s plumbing section. This section should include a photo of the shut-off valve as well as the location. 

Lastly, if the preceding techniques fail, there may be another valve, known as a curb valve. It’s placed at the start of your water main. Look at the borderline of your property and the street or sidewalk. Then, locate the metal or plastic utility box trap door. It is positioned at ground level. 

Step 2: Test Your Main Shut-off Valve

Next up, you’ll need to test the main shut-off valves before starting. Let’s start off with the process- 

First, turn the valve knob to the left (open) and to the right (closed). Then, check to see if water flows normally while the valve is open. Also, water won’t flow at all when it is closed. 

If the shutoff valve is stuck or won’t close completely, it should be fixed or replaced.

To clear it out, is there any white, turquoise, or brown residue on the valve’s exterior? That implies your valve is most likely rusted. Older valves are more prone to mineral deposits as stated before.

Next, look for any dampness around the pipe or on the floor underneath it. If you discover any signs of a leak, seal the shut-off valve as soon as possible. 

Use that fixture only once the leak has been repaired. It’s possible that you’ll need to employ a skilled plumber. He will assist you to locate the leak’s source and repair it properly.

Step 3: Remove the Valve and Stop The Leakage

Finally the last step for replacing the old valve. In this step, you have to remove the old valve. Before you replace the old valve, it’s necessary to buy a new one. Preferably a ball valve should be installed because it’s the most reliable type. 

Removing the Old Valve

Examine the “bonding jumper” in the electrical system. It attaches a clamp on the home side of the meter to a clamp on the street side. 

It’s fine if you can unscrew the old valve while the bonding jumper wire is still in place. If you can’t, don’t disconnect it.

Installing a larger piece of copper wire and two new clamps are the safest approach to solve this problem. It should be 6AWG for 100-amp service and 4 AWG for 200-amp service.

Remove the short bonding jumper after that. You’re ready to turn off the water and reinstall the valve at this point.

Turn off the water supply valve on the street side of the home. Loosen the connection nut and remove the old valve. You’ll need to disconnect the coupling on the “house side” of the water meter. Then remove the valve.

Stop the Leakage 

A 3/4-inch pipe is most likely running to and from the leaking valve. Purchase a threaded replacement ball valve rather than the outdated gate-style valve.

Install the new ball valve and replace the leather washer. You can use Teflon tape or pipe dope on the threads. Tighten the coupling nut. After that turn on the water and check if the valve is leaking. 

Buy a Leather Washer 

Since you have to replace the leather washer, you have to get a new one. Leather washers are difficult to come by. So search for them in a plumbing supply store or search online. 

Some plumbing supply houses sell neoprene washers but neoprene ultimately dries up and cracks. So, I highly suggest going for a leather washer. 

Here’s some leather washer we’d recommend:

Product 1
Product 2

How To Replace Your Unit’s Main Shut-off Valve

Replacing the unit’s main shutoff valve isn’t a big deal. You can do it yourself without struggling too much. The valve might be stuck or broken. 

First, open the valve, then cut the supply line. When you cut the supply line, use the shark bite ball valve in the open position. Put PVC glue on the pipe and push the “open valve” on the pipe. 

There is PVC glue that can be used to stop water leakage. Let the glue set. Close the valve to stop the water flow. Now reconnect your new valve to the water meter.  

Another option is to add a second valve downstream of the first valve. This is far easier than the first option. 

That’s all you need to know to replace your main shutoff valve without turning off the water. Stick to the given instructions and you can do it. Again, Don’t forget to take help from a professional if you’re not swift enough to fix this. That too without spilling gallons of water. 


Question: Do you need to shut off water to change the faucet?

Answer: Yes you need to shut off the water valve to change the faucet. 

Question: How do you replace water shut off without turning off water?

Answer: It’s not recommended at all. If you must turn on all the taps in the house, it decreases the water pressure. 

Question: How much does it cost to replace the main water shut-off valve?

Answer: You’ll need around 375 dollars to 600 dollars to replace it. 


Now you know how to replace the main shut-off valve without turning off the water. We’ve given you the complete guide. But if you face issues, get a plumber to fix it. 

Or replace the main shutoff valve without cutting off the water with a professional’s help. It’s an expert’s job. Not everyone has the skills to do it. 

We hope we can help you with our guide. Take care!