PVC to metal connection "seeping": advice?

Old 10-05-16, 08:12 AM
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PVC to metal connection "seeping": advice?

I sweat soldered a brass tee into my underground copper water supply line, then threaded a 3/4" male PVC adapter into the tee. Having read lots of opinions on how to seal the threads, I elected to go with 4 wraps of new Craftsman teflon tape and no pipe dope. I used a big crescent wrench to tighten the adapter all the way to where the plastic shoulders were just starting to deform. I then cemented a short piece of PVC pipe into the adapter, capped it, turned the water back on and hoped for the best.

The good news is there's no leaks in my solder connections. However, the small gap between the shoulders of the PVC adapter and the top of the brass tee is somewhat wet. I was hoping this was condensation but that's not the case. It sometimes oozes down the side of the tee but never really forms a drop of water on the bottom of the tee....I've placed a plastic bowl under the tee and there's never ANY water it after 12 hours. I suppose it evaporates before it can form a drop on the bottom of the tee.

I honestly don't know whether to leave it as is and cover it back up, or to shut the water off and attempt to unscrew the PVC adapter, clean out the old teflon and put another adapter in it with four wraps of tape PLUS a healthy dose of pipe dope.

If I bury it as is, what are the odds the seep will turn into a full blown leak as time goes by?

If I try to unscrew the adapter, what are the odds that it will break, leaving the PVC threads inside the brass tee? If that happens, what's the best method of getting them out? Saw part of the way through them with a Hacksaw blade and then use a chisel??? Would using Liquid Wrench or PB BLASTER on the plastic threads be advisable before attempting to remove the adapter?

Hopefully some of you pros have run into a similar problem and can advise me as to which approach to take.
Old 10-05-16, 08:23 AM
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Yes, I would take it apart and redo. Little chance the threaded adapter will break; they usually unscrew easily.

There is a tendency for people to over tighten threaded PVC. Finger tight and then 1 or 2 turns max. If you over tighten the fitting will deform and often even crack, right away or later. I would not reuse the fitting. People used to the way threaded metal pipe gets really tight will over tighten PVC every time because the fittings just don't do a hard stop like metal.

I don't use tape on threaded PVC, only rectorseal. The tape primarily acts as a lubricant, which you don't need on PVC; the dope actually helps seal.

Good luck!
Old 10-05-16, 08:29 AM
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You should be able to unscrew the PVC fitting, that's the nice thing about brass. You can also leave it as is since it's not actually dripping, but I wouldn't recommend that even though it might not get worse.

On any type of water pipe, I always use tape plus dope. The dope I use is 100% Teflon paste or pipe dope containing Teflon.
The fittings do not need to be overly tight, just snug it up and maybe 1/2 turn. It's not good to force additional turns.

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