A threaded cpvc coupler leads into a threaded steel reducer which in turn leads the hot water (irrelevant) but I have been using teflon tape to wrap around the cpvc's threaded male end to go into the receiving end of the threaded steal reducer.

What is problem? Have a leak? What size are u talking about?

Chuck

Yep, teflon tape is the way to go with plastic threads. Actually the only way to go. Liquid pipe dopes are not to be used on plastic threads. If you are experiencing a leak, try a few extra wraps of telfon. If the leak persists, I would suggest trying a new cpvc male adapter.