CPVC Incompatibility

All FORMUFIT Products are designed to fit Nominal Pipe Size (NPS) size, white, Schedule 40 PVC pipe.  However, many hardware stores and home centers carry a different style of pipe called CPVC, also known as Copper Tube Size (CTS) plastic pipe, which is not compatible with FORMUFIT and other brands of PVC fittings.

cpvc vs. pvc comparison

I ordered (1/2, 3/4 or 1 in.) fittings from FORMUFIT, but they don't fit my pipe?

Check to see if the pipe you are trying to use is CPVC.  You can do this by checking the color of the pipe:  CPVC is a gold/yellow/tan color, whereas Schedule 40 PVC plumbing pipe is a dull white.  Also, markings on the pipe with the following acronyms or names will be present for CPVC:

  • CPVC
  • CTS or Copper Tube Size

CPVC Pipe Markings

If the above are not marked on your PVC pipe, you may have ordered the incorrect size for your Schedule 40 PVC pipe.  In that case, please see our Important PVC Pipe Size Information page.

Whats different about CPVC and why can't I use it?

CPVC was designed as a replacement for copper plumbing tubing, with a water-potable and less-expensive plastic solution.  It is designed to fit into the exact same holes and locations where existing copper pipe is being replaced, so it has a smaller outside diameter (OD) than typical white, Schedule 40 plumbing-grade PVC.   Since CPVC pipe uses a different measurement system and is smaller than their Schedule 40 counterparts, it is not compatible with FORMUFIT fittings and accessories.

Is there anything I can do if my CPVC pipe wont work?

Yes.  You can change your pipe from CPVC to the Schedule 40 PVC pipe of the equivalent size.  If you have not yet cut your pipe, most home centers and hardware stores will allow you to exchange your CPVC pipe for the Schedule 40 equivalent size.  This is usually the less expensive alternative than returning your items to FORMUFIT, as we do not carry CPVC-compatible products.