Copper compression fittings create a watertight seal on copper pipes by mechanically compressing a compression ring (usually a ferrule) onto the pipe surface. Here's a step-by-step guide on how to use them:
Steps for Using Copper Compression Fittings:
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Prepare the Copper Pipe:
- Cut the copper pipe squarely using a tube cutter. Avoid using a hacksaw, as it can leave burrs.
- Deburr the inside and outside of the pipe using a deburring tool or reamer. This ensures a smooth surface for the ferrule to grip and prevents damage to the O-ring (if present).
- Clean the end of the pipe with fine steel wool or emery cloth to remove any oxidation or dirt.
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Assemble the Compression Fitting:
- The compression fitting typically consists of three parts:
- The fitting body: This is the main part of the fitting, with threads on the inside.
- The compression ring (ferrule): This is a small, usually brass or copper ring that will be compressed onto the pipe.
- The compression nut: This nut screws onto the fitting body and tightens the ferrule.
- Slide the compression nut onto the copper pipe. Make sure the open end of the nut (the threaded end) faces towards the fitting body.
- Slide the compression ring (ferrule) onto the copper pipe after the nut, with the tapered end facing the fitting body.
- The compression fitting typically consists of three parts:
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Insert the Pipe into the Fitting:
- Insert the end of the prepared copper pipe into the fitting body as far as it will go. Ensure the pipe is fully seated within the fitting. It should be straight and making firm contact with the stop inside the fitting body.
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Hand-Tighten the Nut:
- Screw the compression nut onto the fitting body by hand until it is snug. Do not overtighten at this stage.
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Tighten with Wrenches:
- Use two wrenches. Place one wrench on the fitting body to hold it steady. Use the second wrench to tighten the compression nut.
- Tighten the nut approximately 1 to 1 1/2 turns beyond hand-tight. You should feel resistance as the ferrule compresses.
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Test for Leaks:
- Turn on the water supply and carefully inspect the connection for leaks.
- If a leak is present, slightly tighten the nut a little more (about 1/8 of a turn). Be careful not to overtighten, as this can damage the fitting or pipe. Retest.
- If the leak persists, disassemble the fitting, inspect the ferrule and pipe for damage, and potentially replace the ferrule.
Important Considerations:
- Overtightening: Avoid overtightening the compression nut. Overtightening can deform the ferrule, damage the pipe, and actually cause leaks.
- Reusing Fittings: Compression fittings are generally not reusable, especially the ferrule. Once a ferrule has been compressed, it may not seal properly if reused. It's best practice to replace the entire fitting, but at least the ferrule, if you need to disconnect and reconnect.
- Proper Pipe Preparation: Correctly cutting and deburring the pipe is crucial for a proper seal.
- Alternative to Soldering: Compression fittings offer a solder-free alternative to joining copper pipes, making them a good option in situations where soldering is not feasible or desired.
