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Shut Off Water Supply — Shut Off Main Water Supply

Beginner3 hours

Part of project

How to Replace a Leaky Angle Stop (Shutoff Valve) Under Your Sink · Step 2 of 9

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In this video

First, locate the main water shut-off valve for your house and turn it off completely. The valve's location can vary, but it's often located outside near the water meter or inside in a basement or utility closet. In the video, the valve is in an access pipe in the yard.

Goal: Plumbing Pipes Repair (Repairing damaged or leaking plumbing pipes.)

  • Confirm the water is off by turning on a faucet elsewhere in the house. If water still flows, you have not shut off the main valve.
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FAQs

What's the single most important safety step to take before I even touch the leaky angle stop?

The most critical step is to shut off the main water supply to your home. This prevents potential flooding and ensures a safe working environment. Always confirm the water is off by testing a nearby faucet before proceeding with any work.

The project is listed as 'beginner' difficulty, but 3 hours seems long for a valve. Is it really that involved?

While replacing an angle stop is beginner-friendly, the 3-hour estimate accounts for prep work like gathering tools, draining lines, dealing with potential seized parts, and thorough leak testing. Taking your time ensures a proper, leak-free installation, so don't rush the process.

I see "Adjustable Wrench" and "Tongue and Groove Pliers" listed. Are these specific tools essential, or can I get by with a generic wrench set?

Yes, these specific tools are highly recommended. An adjustable wrench helps securely tighten the compression nut on the new valve without stripping it, while tongue and groove pliers (like Channellock) provide a strong grip for holding the valve or pipe steady. Using the correct tools prevents damage and ensures a tight, leak-free connection.

This project specifically mentions installing a "compression-style valve." Are there other types of angle stops, and why is this type recommended for a DIYer?

Yes, other types include soldered (sweat) and push-to-connect (SharkBite) valves. Compression-style valves are ideal for DIYers because they create a watertight seal by compressing a ferrule onto the pipe, requiring only basic hand tools and no specialized skills like soldering, making them relatively easy to install.

Transcript
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this, but switching out the cartridge is really easy. First thing you'll need to do is turn off the main water that goes into the house. Mine is just outside my house. It's different for every house, so you'll just need to find out where yours is and shut it off.

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