: I'm re-plumbing the master bath. The walls are open, so I decided to re-plumb the copper to cpvc. I got advice to get the qest couplings to go from copper to cpvc. I am a little afraid to do this. I have already cut and sealed everything up to the point of just putting the coupling on the copper. Has anyone done this to their home and has it worked? And exactly how do these couplings stay on the copper pipes and not leak? Do I use sealant on the copper? The directions say not needed. Thanks
Do not use these. Solder a copper female adapter on the copper and use a brass x slip CPVC male adapter (or vise versa). Do not use a CPVC fitting with plastic threads.