Again,10 years in a plumbing warehouse,I know all of this.The warehouse I work in sells CPVC drain fittings.Dan Feller;3428503; said:The difference is in the fittings. ABS and DWV PVC fittings are considerably different from PVC, CPVC, or PEX fittings.
In drain fittings tees and wyes are directional, they have an "up" and "down" (except clean-out tees, which are omnidirectional). Ells come in long, medium, and short radius sweeps. There are also specialized drain fittings such as a low-heel tee and various flanges.
This thread however,is not about drainage.
