On Feb 16, 8:58 am, "
wrote:
Hi everyone,

I redid some plumbing in my basement and it went well except for one
thing:

I can NOT get one area to stop dripping. It's a spot in a hot water
line to the shower where I joined 1/2 inch
CPVC to 1/2 inch copper. I used a male, threaded CPVC fitting into a
female, threaded copper fitting.
I used pipe dope and tightened it as much as I could. Any more tight
and it probably would break.

I have redone this fitting three times and it just won't seal, always
drips. As I said, I used pipe dope one time.
One time I used teflon tape. I was told that both of these are ok to
use in this situation.

Now, oddly enough, when I take a shower and the pipe gets good and
hot, it stops dripping.
When it cools, it starts again as if the expansion was sealing it.

I'm out of ideas.

Help?

Thanks

Whenver I need to thread two parts together I put them together with
nothing on them and tighten them up. Then I take them apart and apply
tape or dope (gas lines). This helps clean and straighten any
irregularities in the threads. You may need to insert a metal male
piece into the copper to clean/straighten the threads. Then use a new
male CPVC fitting with tape.

Could be that the CPVC fitting is bottoming out before the threads can
get tight. Check this and trim a little off of the end if this is the
case.