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Shut Off Water Supply — Shut Off the Water Supply

Beginner2 hours

Part of project

Replace Your Bathroom Faucet: Easy Guide · Step 1 of 5

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Before beginning any work, locate the hot and cold water shutoff valves under the kitchen sink. Turn the handles clockwise until they are fully closed to stop the water flow. Open the faucet above to drain any remaining water from the lines and confirm that the supply is completely off.

Goal: Prepare for Repair

  • Ensure both hot and cold valves are fully closed. If they don't shut off completely, you may need to shut off the main water supply to the house.
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This Old House

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FAQs

The project states 'beginner' and '2 hours'. Is this realistic for someone with no plumbing experience?

Yes, replacing a bathroom faucet is generally beginner-friendly if you follow instructions carefully. The 2-hour estimate is for a smooth installation; seized nuts or tight spaces can extend this, so allocate a bit of extra time. Take your time and don't rush the steps.

Is a basin wrench truly necessary for this project, or can I just use my adjustable wrench?

A basin wrench is highly recommended, as it's designed to reach and grip the often-tight mounting nuts in the confined space under a sink. While an adjustable wrench might work for accessible nuts, the basin wrench significantly simplifies this often frustrating step, especially for older faucets.

What's the most common mistake beginners make that leads to leaks after installing a new faucet?

Not properly tightening the supply line connections is a common cause of leaks. Ensure they are hand-tight, then use a wrench for an additional quarter to half turn, being careful not to overtighten and strip the threads. Always use new supply lines, often included with your new faucet.

What should I do if the old faucet's mounting nuts are corroded or stuck and won't loosen?

First, apply a penetrating oil (like WD-40) to the nuts and let it sit for 15-30 minutes. If they still won't budge, you might need to carefully use a hacksaw or oscillating tool with a metal blade to cut through the nuts or bolts, but exercise extreme caution to avoid damaging the sink or surrounding plumbing.

Transcript
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So first thing is first, make sure you shut off both the cold and the hot water valve underneath the sink.

Auto-generated transcript. May contain errors.