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5 Easy Steps to Cap a Copper Pipe

5 Easy Steps to Cap a Copper Pipe

Are you looking for a quick and straightforward way to cap a copper pipe? Traditional methods such as torch soldering can be complicated even for the most experienced home plumber.

Push to connect fittings are a faster, no-fuss alternative to soldered or mechanical connections. These fittings might be pricey but for most homeowners, the ease of use outweighs the cost. With push-to-connect fittings, you can cap any copper pipe in a few minutes.

Read on to find out how to cap a copper pipe without breaking a sweat.

Understand How Push To Connect Caps Work

Plumbers user the term push-to-connect to refer to a pipe cap used instead of soldered or mechanical pipe capping methods. An example of a popular push-to-connect brand is SharkBite, a name people commonly use to refer to any type of push-to-connect fitting.

Also known as push-to-fit, these caps comprise of a sharp internal barns and seals that hug the pipe tightly preventing leaks. Some local plumbing codes may prohibit using push-to-connect caps so you should check with the plumbing regulations in your area.

There are many types of push-to-connect fittings. Common ones include adapters, couplings, and elbows, all of which do as good a job as torch soldering while saving you the time and effort.

Things You Will Need for capping copper pipe

  • Push-to-connect caps
  • Pipe cutter
  • Metal file
  • Tape measure
  • Maker
  • Emery cloth
  • Piece of rag

Step-By-Step Guide On How To Cap a Copper Pipe

Follow these easy steps to learn how to cap a copper pipe using push-to-fit caps.

Step 1: Shut off the water and drain the pipe

Shutoff the main water supply. Since you will cut the pipe, shutting off the water supply at the main shutoff valve lowers the pressure in the pipe and ensures you do not flood the house.

Ensure that the pipe has as little water inside as possible. Draining the pipe minimizes the amount of spilling water when you cut the pipe. You can drain the pope by turning on a faucet lower than the pipe or a tap outside the house.

Step 2:  Cut the pipe

When cutting the pipe, ensure that the cut is clean and straight so the push-to-connect cap will fit snuggly. A tubing cutter is a better alternative to a hacksaw if you want to make a clean cut on your pipes.

Pro tip: Leave enough pipe to avoid adding and extension when you need to reconnect the piping.

Step 3: Wipe the pipe end clean

A clean pipe is the secret to a snug cap; any metal chippings will prevent the push-to-connect cap from fitting properly, resulting in leaks.

Use a rag to clean the cut pipe, removing the metal chippings. File down any rough edges so there are no spaces between the pipe and sealing cap. A mental file will get the job done but if you opt for an emery cloth be gentle to avoid sanding down the pipe and decreasing its original diameter. Making the pipe less round and smaller than its original size will prevent the cap from fitting properly.

Step 4: Mark the depth of each end of the pipe

Measure the length of the push-to-connect fitting using a tape measure. Transfer this measurement to the pipe and put a marking that will show you how far the cap should go so you can know that it has fit completely.

Next, simply insert the open end of the cap into the end of the pipe you want to cap. Push the fitting along the pipe until it reaches the depth mark you had made on the pipe. Listen for a click, which indicates that the pipe has tapped the end of the cap.

Step 5: Check that the cap fits

Ensure that the pipe does not leaks at the point of capping. There is nothing worse than assume that your SharkBite capping is secure only to come back to a flooded room or basement.

To test that the cap fits, turn the water shutoff valve back on, allow the water to start flowing again, and check for leaks around the capped area.

Most push-to-fit caps come with a special tool that you can use to remove the fitting anytime. The tool is typically a small plastic equipment that you push onto the cap, which eventually releases it.

That’s it! Now you know how to cap a copper pipe using a SharkBite or push-to-connect fitting.

If you want a permanent seal, you are better off using the soldering method to cap your copper pipes. In the next section, I will show you a simple method to cap a copper piper with solder. Read on to learn.

Step-by-Step Guide on How To Cap a Copper Pipe By Soldering

Push-to-connect fittings are easy to use but they are best used as a temporary rather than permanent solution. These fitting can slide off if there is a lot of pressure inside the pipe, resulting in leaks and potential flooding if you don’t notice the leaks early enough.

Soldering is a more demanding process but it is also more secure if you want to permanent cap your copper pipe. Follow these steps to cap a copper pipe using the soldering method:

Things You Will Need:

  • Propane torch
  • Lead-free solder wire
  • Copper cap fitting
  • Pipe cutter
  • Thin rubber hose
  • Paste flux and brush
  • Emery cloth or steel wool
  • Protective sheet metal
  • Bucket
  • Fire extinguisher
  • Damp towel

Step 1: Cut and drain the pipe

First, turn off the water from the main supply line before proceeding to cut the pipe. Release pressure inside the pipe by opening a faucet and allow the pipe to drain as much as possible.

Next, cut the pipe using a pipe cutter and use the attached reamer to ream the pipe’s interior. The reamer helps to remove burrs from the pipe’s end, leaving a smooth suffering for capping.

With the pipe cut, ensure that it is completely drained. Insert a thin hose into the open end of the copper pipe. Set up a siphon by sucking on the free end of the hose then hold this end over a bucket to drain the water.

There should be an empty space of about 25 inches inside the hose from the open side of the pipe. This vacuum tells you that the copper pipe is completely drained.

Step 2: Dry and clean the cap and pipe

Cleanliness is the key to a strong, leak-free soldered joint. Use an emery cloth or steel wool to scrub the copper pipe gently until the metal surface is shinny. Scrub and brighten the copper cap the same way.

The pipe and cap should be free of debris that could compromise the strength of the soldered joint. Avoid touching the pipe’s surface and the inside of the cap cleaning them.

Even after draining the pipe, ensure that the inside of the pipe is completely free of water traces. Use a heat gun to dry the pipe and remove lingering steam.

Step 3: Apply solder paste flux

Use the flux brush to apply paste flux on the cut end of the pipe and the interior of the copper cap fitting. Flux helps to seal out air to prevent oxidation, clean oxidized metal left on the pipe, and improve amalgamation if you use liquid solder. Apply the paste liberally for the best outcomes.

Step 4: Protect combustible surfaces

Use a piece of sheet metal to protect drywalls, wall studs and other combustible surfaces against heat from the propane torch. Be sure to have a fire extinguisher close by. Slip the cap fitting over the copper pipe.

Step 5: Apply heat to the cap and pipe

Light a propane torch, ensuring a strong, consistent, cone-shape flame with a blue center. Then, unwind 7-inches of solder wire from the roll.

Next, bring the propane torch close to the joint between the pipe and cap fitting and apply a steady amount of heat. Focus the heat on the joint to avoid overheating the reminder of the pipe.

Step 6: Apply solder to the hot joint

Place the tip of the solder wire on the pipe where it meets the edge of the cap fitting. The joint should be hot enough to melt the solder wire.

Feed some more solder around the joint and observe as the wire melts. Remove the heat but keep feeding the solder until you notice a glowing ring around the joint at the edge of cap fitting. Also look out for extra drops of solder on the pipe—this is a sign of a well soldered joint.

Step 7: Cool the soldered joint

Keep an eye on the joint for a few minutes and ensure that there are no tiny holes on the soldered joint. These tiny holes can end up being a big problem if your pipe starts to leak. Apply a damp cloth over the soldered seam to cool it.

Step 8: Test the integrity of the soldered joint

After the soldering job, check for potential leaks. Turn off on the shutoff valve to allow water to flow through the piping system. Observe the joint keenly to ensure there are no pinholes through which water can leak.

There you go! That’s how you cap a copper pipe using the more permanent and leak-proof soldering method. Good luck with your project!