PVC to copper joint

[carverelli]

Guys, here's my dilema. I've been working for xyz company for 3 months. I'm a licensed commercial journeyman since '96 and have somewhat of a diverse background. I;ve plumbed hundreds of houses, service calls, institutions(jails), installed several decent sized hydronic systems,etc. This last week on a new grocery store w/ 3" water service I used a 3" copper male
adapter mated to a female pvc adapter about 6 ' outside the building foundation. This is so wrong I can't begin to tell you. Several places in the code it prohibits pvc female fittings unless joined by pvc male fittings. We pressure tested to 70lbs for three days and it held . I voiced my opinion and it fell on deaf ears. "WE've had problems w/ the pvc male adapters breaking off" they said. How long before the pc fip splits?
And how would you make the connection? In the past , I've used a sch 80 nipple w/ one side of the threads cut off and then glued a regular coupling to the smooth part of the nipple. That would be stronger than a mip.

[Quescodeplumb]

Your correct, the best way I know of to join the two in that situation is a copper female adaptor and screw a pvc sch 80 nipple into it, cut off the other threads and glue a pressure pvc coupling on the other side or in a tight situation a telescopic coupling might help. The repair you made may or may not last, depends on how hard you cranked down into the pvc female adaptor, and how you supported the repair underground to prevent movement. Sounds like company xyz wanted you to use what was on the truck because what was done, and what you know you should have done has no labor difference. Sounds to me like if your opinion doesn't count at company xyz and it's your install maybe it's easier to work for company abc who respects the voice of there installers.

[carverelli]

It wasn't a repair. New construction. I was absolutely dumbfounded they wanted me to do this. The inspector didn't like it, but didn't have the balls to make uss change it. He passed it off to the engineer who came back w/ " I/we don't have a problem with a female pvc adating to copper unless it violates a particular code". Well it does. My only hope is it will leak and manifest itself before they have ot patch the asphalt.

[plumbdog10]

My personal preference when joining large PVC and copper is to use flanges. I'm just not a fan of threaded PVC, although I'll use it on small exposed locations.

the dog :cool:

[imported_PLUMBER RICK]

writing from costa rica. i've had pvc male and femal shear off months later. a mechanical joint that is properly braced to keep from pullin apart will work great. the sch. 80 nipple will work good too.

rick.
ps. it's raining here.

[ToUtahNow]

Originally posted by PLUMBER RICK:
writing from costa rica. i've had pvc male and femal shear off months later. a mechanical joint that is properly braced to keep from pullin apart will work great. the sch. 80 nipple will work good too.

rick.
ps. it's raining here. Vacationing in Costa Rica and you're online. YOU NEED TO GET A LIFE!

Mark :D

[plumber]

Agreed flange joint is best.

One thing you might be able to do since you have made the installation already is to put a couple of stainless steel hose clamps around the outside of the fitting to give the PVC material a little back up strength. It should buy your installation a little more time, hopefully enough time to find a smarter boss.

You are correct that a female PVC fitting should never be used over a metal male fitting.

I have found that most MIP PVC to metal FIP failures were due to the installer applying too much torque to the fitting. Its just one more reason to use copper service lines. Saving a buck often costs two.