CPVC threaded coupling to Brass nipple is leaking
I just installed a new sink in my garage using CPVC for the plumbing run. Never used CPVC before. Where I came through the wall, I used a CPVC female threaded fitting with ears on it to fasten to the wall stud. I then screwed a 4" brass nipple to it with teflon tape and attached the valve to the other end with teflon tape as before. I now notice a slight weeping or sweating leak at the CPVC fitting. There is a rubber washer inside the CPVC fitting, so now I'm wondering if I just didn't screw it down tight enough. How tight do I screw the brass nipple into this CPVC fitting? Am I not supposed to use teflon tape since there is a washer inside the fitting? I'm a bit concerned that if I really reef the nipple down tight, it might crack the CPVC fitting itself.
Thanks for your help!