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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! 

It would be best if you replaced the main valve in your home and another by the street.  

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

Replacing the main shut-off valve is relatively easy and requires only three steps. 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 type of shut-off valve. There is also a single main shut-off valve. This allows you to turn off the water in your entire house. 

If your main shut-off valve is leaky, try tightening it 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 also need to replace the street-side valve. 

Is your home old? TSaddle valves might leak because it’s an old fixture. Then you might have an old main shut-off valve too.

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 shut-off 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 shut-off 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 shut-off valve inside your house. It’ll usually be situated on the home’s perimeter. This is where the water plunges into the house first. Also, the water main generally starts at the street and runs straight to your house. 

You can check the property inspection report if you cannot discover the shut-off valve. 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 and the location. 

Lastly, another valve may be called a curb valve if the preceding techniques fail. 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 with the process- 

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

It should be fixed or replaced if the shut-off valve is stuck or won’t close completely.

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. You may need to employ a skilled plumber. He will assist you in locating the leak’s source and fixing 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, buying a new one is necessary. 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 OK to unscrew the old valve while the bonding jumper wire is still in. 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.

Turn off the water supply valve on the street side of the home. You’ll need to disconnect the coupling on the “house side” of the water meter. Loosen the connection nut and remove the old valve. 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. Tighten the coupling nut. After that, turn on the water and check if the valve is leaking. You can use Teflon tape or pipe dope on the threads. 

Buy a Leather Washer 

Since you must replace the leather washer, you must 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 are some leather washers we’d recommend:

Product 1
Product 2

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

Replacing the unit’s main shut-off 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 shut-off 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. 

FAQs

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

It would be best to shut off the water valve to change the faucet.

How do you replace the water shut-off without turning off the water?

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

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

You’ll need around $375 to $600 to replace it. 

Conclusion 

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 them. 

Or replace the main shut-off 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!