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Connect Water Supply Lines — Install the New Supply Line

Beginner

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How to Fix a Leak at a Faucet Supply Line Connection · Step 4 of 5

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Connect the integrated hot and cold water supply lines from the faucet to the corresponding angle stop valves on the wall. The hot line is typically marked with a red indicator. Thread the connections on by hand first to prevent cross-threading. Then, use an adjustable wrench or finish pliers to give each connection a final quarter-turn to ensure a snug, leak-free seal.

Goal: Attach faucet to water supply

Used in this video

  • Adjustable Wrench (Tool Type: Adjustable Wrench)Tightening the supply line nuts.
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FAQs

How long does a beginner typically need to fix a faucet supply line leak, and what's the most common hold-up?

For most beginners, this project takes about 30-60 minutes. The biggest time-consumer is often preparing the work area, ensuring the water is fully off, and carefully tightening the new connections to avoid overtightening or cross-threading.

The project mentions a 'Braided Polymer Faucet Supply Line.' Are there other types, and how do I ensure I get the right replacement?

Yes, supply lines come in various materials like braided stainless steel or PEX, which are also durable options. The most critical step is to match the length and the connector sizes (e.g., 3/8 in. compression x 1/2 in. FIP) of your new line to your existing one and the connections on your faucet and shut-off valve.

I've replaced the supply line, but it's still leaking slightly after installation. What's the first thing I should check?

First, ensure both nuts are snug but not overtightened; over-tightening can damage internal washers or threads. Confirm the supply line is seated straight without cross-threading, and visually check that the small rubber washer inside the faucet connection is present and intact, as this creates the primary seal.

Is it ever okay to just tighten the old leaky supply line connection instead of replacing the entire line?

You can attempt a slight turn with your wrench to see if it stops the leak, but if it's an older line or already tight, this often isn't a permanent fix and could worsen the leak. Replacing the inexpensive supply line ensures a fresh, reliable seal, especially if the internal washers are worn or compressed.

Connect Water Supply Lines — How to Fix a Leak at a Faucet Supply Line Connection (Step 4, Video 2) | Stesso