[foffad62]

hot and cold water lines for sink. copper to cpvc connection leaks-cpvc connetor screwed to copper on one line and metal connector screwed to copper on other. tightened till I was sure they were about to break. Used teflon tape, one layer. Leaks, leaks, leaks. What am I doing wrong other than not calling a professional?

 

[AllanJ]

hot and cold water lines for sink. copper to cpvc connection leaks-cpvc connetor screwed to copper on one line and metal connector screwed to copper on other. tightened till I was sure they were about to break. Used teflon tape, one layer. Leaks, leaks, leaks. What am I doing wrong other than not calling a professional?

White Teflon tape, you're supposed to use three or four layers.

There is a thicker pink Teflon tape, I think that is for gas pipe only.

You're not supposed to have to use all your might and main to tighten it.

 

[Grampa Bud]

Four to six turns with the teflon tape on the male threads is the preferred amount and you could use some pipe dope on top of the teflon tape if the threaded fittings have been previously over-tightened. You may also have to replace any threaded cpvc fitting because they become brittle over time and may develope small cracks in the threaded portion of the fitting especially if they have been over-tightened on any metal thread.

 

[secutanudu]

One layer of teflon tape is not enough. 4-6 wraps of that white stuff plus pipe dope on the outside of the tape is what I'd do, though I use 3-4 wraps of the blue (thicker) tape + pipe dope.

 

[Thurman]

IMO: ANY female connector screwed to male copper is notorious for leaks. Remove this connection if possible, clean all threads as well as you can and use a paste type thread sealant. Plumbing supply houses sell a sealant just for these connections.