How to Connect a Black Water Line to PVC

Black water lines can be ABS drainlines or black iron water supply lines.

In older homes, you are likely to encounter a black colored drain pipe, which signifies ABS piping. Today, it is difficult to find ABS pipe and fittings and you need to connect PVC piping to the existing black piping of your home. ABS piping is not the only type of black piping you are likely to encounter. Black iron water pipe is also found in older homes. To distinguish between the two, as simple test needs to be performed. No matter which type of piping your encounter, the connection between the black pipe and the PVC will be the same.

Things You'll Need

• Hammer
• Flexible transition coupling
• 5/16-inch, 60 inch-pound torque wrench

Instructions

1. Lightly tap the black water pipe with the hammer. If you hear a ring, the black pipe is black iron or if you hear a dull thud, the black pipe is ABS plastic.

2. Loosen the cable clamps of the flexible coupling fitting by turning each clamp screw counter-clockwise with the 5/16-inch, inch-pound torque wrench.

3. Slide the end of the flexible transition coupling marked for the black water line onto the end of the existing black pipe and tighten the clamp screw resting over the black water line clockwise to hold the transition fitting to the black water pipe.

4. Push the end of the PVC pipe into the other end of the flexible transition coupling and tighten both clamp screws to 60-inch-pounds of torque with the 5/16-inch torque wrench to complete the connection between the black water and PVC pipes.

References

• Reader's Digest: How to Connect a PVC pipe to ABS Pipe
• Fernco: Flexible Coupling Installation Instructions