How to Connect PVC Pipe to Copper Pipe

Transition to PVC pipe from copper pipe by connecting a PVC threaded female adapter to a copper male threaded adapter. This connection allows you to use much less expensive PVC line to lay a sprinkler or irrigation system, a domestic water supply line or a swimming pool plumbing system. To make a solid, leak free plumbing connection, follow these steps.

Difficulty: Moderate

Instructions

Things You'll Need:

• Hacksaw
• Emery cloth
• Copper threaded male adapter
• Solder
• Soldering flux
• Propane torch
• PVC threaded female adapter
• Teflon tape
• Pipe wrench
• PVC Purple Primer
• PVC pipe cement

1. Turn the water supply off and hacksaw the copper pipe off at the point where you want to attach the PVC line. Let the water drain out completely.

2. Dry the copper line inside and out with a rag, then use the emery cloth to sand the copper to about 2 inches back from the cut. Make sure the cut is smooth and last 2 inches of the copper pipe is shiny and clean all the way around.

3. Hold the copper male adapter by the threads and sand the inside surface of the slip end (the end opposite from the threads) with the emery cloth until the entire inside surface is shiny and clean.

4. Brush a thin coat of soldering flux around the copper pipe to about 1 inch back from the cut. Apply a thin coat of the flux around the entire inside surface of the copper male adapter slip joint.

5. Slide the slip side of the copper male adapter onto the copper pipe as far as it will go and twist it a half turn to make sure the flux is evenly distributed on both the pipe and the inside of the slip joint.

6. Apply heat with the propane torch evenly around the entire circumference of the slip joint. When the flux begins to melt and drip from the connection, apply the solder to the point where the fitting and the pipe meet. Continue to apply heat and be sure the solder melts and flows into the joint evenly all the way around.

7. Allow the copper fitting and pipe to cool, then wrap Teflon tape several times evenly around the copper threads. Cover all the threads.

8. Turn the PVC threaded female adapter onto the copper male threads and tighten it with your hand until you can no longer turn it. Use the pipe wrench to finish tightening the joint.

9. Prime the inside of the PVC slip joint with Purple Primer. To attach the PVC pipe, prime the outside of the PVC pipe with Purple Primer, then coat both the outside of the PVC pipe and the inside of the PVC slip joint with PVC pipe cement. Slide the PVC pipe into the PVC slip joint as far as it will go and hold it in place for a minute until the cement sets.

Tips & Warnings

• Clean, dry surfaces are the key to making good, solid solder joints with copper.
• Use schedule 40 or schedule 80 PVC fittings and pipe, especially on any pressurized system, such as a water supply line or a pool plumbing system.
• Never connect a PVC male adapter to a copper female adapter. In the presence of heat or water friction, PVC can shrink dramatically and the joint will eventually fail.
• Check your local building code to be sure PVC is acceptable for the application you are installing or repairing.