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Restore Water and Check for Leaks

Beginner3 hours

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How to Install a Water Hammer Arrestor to Stop Banging Pipes · Step 5 of 5

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Slowly turn the cold water shut-off valve counter-clockwise to restore the water flow. You will hear whooshing sounds as air is purged from the system. Turn on the faucet and let the water run. The first water may be dark with carbon fines, followed by cloudy water from air bubbles; this is normal and will clear up. Carefully check all new connections for any drips or leaks.

Goal: Turn on water, flush the filter, and verify no leaks

  • It is normal for the water to be dark at first as the filter activates. It is also normal for the water to appear cloudy for about a day due to air bubbles. This is perfectly safe.
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FAQs

How do I accurately identify the source of water hammer before installing the arrestor?

Listen carefully for the banging sound when a specific faucet, toilet, or appliance (like a washing machine) shuts off abruptly. You can also try gently touching the water lines near suspect fixtures to feel for vibrations when the noise occurs. Installing the arrestor as close as possible to the identified source will yield the best results.

What crucial safety steps must I take before cutting into the water line?

Always turn off the main water supply to your entire home first. Then, open the lowest faucet in your house (e.g., in a basement or outdoor spigot) and the highest faucet to completely drain the water from the pipes. This prevents unexpected water leaks and potential injury while you work.

Do I need special tools to cut copper pipes, and how do I ensure a leak-free connection?

Yes, a copper pipe tubing cutter (e.g., AUTOCUT 1/2 in.) is essential for a clean, straight cut. After cutting, use a reamer and deburring tool (like the Husky 1-5/8 in.) to smooth the pipe's interior and exterior edges. This deburring step is critical for proper sealing and preventing leaks, especially with push-to-connect fittings.

What's the best way to prevent leaks when installing the tee fitting and water hammer arrestor?

Ensure the pipe ends are perfectly clean, smooth, and free of scratches or burrs. Use a depth gauge (like the Tectite Depth Gauge) to mark the correct insertion depth on the pipe for push-to-connect fittings, ensuring it's fully seated. For the arrestor's threaded connection, apply several wraps of PTFE plumber's tape (Harvey 1/2 in. x 260 in.) clockwise to the male threads before tightening.