Metal Male Threads to PVC leak (Main water line)

[SamuelD47]

Hello,

I was wondering if you guys could help me out with a problem as I don't know much about plumbing.

There was a leak coming from under my yard, so I dug it up and it turns out that the main water line to my house was leaking. The leak was coming from a compression repair coupling that someone (Probably the previous house owner) put there. So I turned off the water to my house, bought a new compression repair coupling and put it on. It failed again after a while. I had to cut it off so now there is around a 10 inch gap between the pipes.

Went to Home Depot and the associates there told me that I cannot use a compression repair coupling on that pipe, because it is High Density Polyethylene(HDPE) and that compression coupling is only for PVC, so I went to a plumbing store. There, I bought 2 HDPE copper couplings (with male threads), 2 copper to PVC adaptors (this is made out of PVC), and some 1-1/2" PVC Sch 40. The idea was to fill in the gap with PVC.

I did all this and its working fine, but the copper to PVC adaptor is leaking. I used 3 rounds of teflon tape on the metal threads and screwed on the PVC adaptor as hard as I could using 2 huge wrenches. It was leaking 1 drop every 20 seconds from each connection, but I don't know what's happening, but now its only leaking every 90 seconds.

Do you guys think this setup will hold or will it get worse overtime, or possible break again? Or should I just save up and call a plumber in a week or two? I can redo and it wouldn't cost that much, but I don't know what else I can do differently. I already spent 8 hours digging up the hose to get enough flex to get it in the coupling

Any help would be much appreciated.
Thank you,
Samuel

[USP45]

Never, and I mean NEVER overtighten any pvc fitting! Snug it is all. Over tightning will cause the plastic to break. You would be better off using a pvc fitting with a brass insert built into it.

[SamuelD47]

Thank you USP45 for the fast response.

So it was possible that I overtightened it? I thought I didn't tighten enough.

I will try again with new adapters, do you recommending anything else besides teflon? I was searching and saw some stuff called rectorseal, but I hope my current set up will self seal.

Thank you

[JohnTelcoMan]

Use tefon tape and pipe dope. I use the stuff with teflon bits in it. I never have a leak. I think rector seal is ok. Just read the back. It will say what it is acceptable to use on.

[USP45]

I swear by Rectoseal. But yes, read the back of the can to be sure it will work for your application

[zosoplumber]

USP45 is right, if you use a metal male threaded adaptor inserted in a female cpvc adaptor, the metal fitting will break the cpvc fitting, like usp said they sell female cpvc fittings with brass threads, they can take the over tighting, or just reverse the adaptions with female metal and cpvc male adaptions.

[drunknmaster]

cpvc is unusauuly use 4 hot water,you must go around aleast 5 to 8 time with the telfon tape,but the is a better way.burp

[SamuelD47]

Thank you all for the responses, I really do appreciate them.

After much internet surfing, it seems like Metal Male into PVC female should never be used. I wish the person at the plumbing store helping me with this would have told me that.

I went ahead and accepted the leak (1 drop every 2 minutes) and buried the pipe with topsoil just incase I have to dig it up later easily. It'll hold now, but I think its going to leak in a year or two.

Are these the kind of couplings you are talking about USP?



http://www.plumbingsupply.com/images...ter-sxfips.jpg

I'm thinking about using these next time it breaks.

or instead of this, do they make female to female adaptors? I was thinking about using that and having male PVC parts instead. (these couplings I bought were already pretty expensive)

Once again, thank you for the responses.
Samuel