Transitioning from Black Poly to PVC

bk406

Well-known member
Dec 3, 2009
2,690
Central Massachusetts
You need to get a brass male adapter fitting that is barbed on one end. Nylon will work, but brass would be better. Might be hard to find 1 1/2 inch fitting thats not nylon poly looks 1 1/2 inch, is it?). If you cant find brass or stainless, nylon will do. Dope up the barbed end of the fitting with teflon pipe dope, put 2 CC clamps on the poly for later, heat the end of the poly with a torch for a second, then push the barbed fiting into the poly. Then, use both clamps around the fitting.

Get a PVC fitting with a female threaded end and a slip coupling on the other. Use the teflon pipe dope and screw the PVC adaptor to the nylon/brass fitting. From there, it's PVC, primer and glue.

A plumbing supply house is really where you need to go. Tell them what you want to do and they can fix you up with the right fittings.
 

bk406

Well-known member
Dec 3, 2009
2,690
Central Massachusetts
JasonLion said:
I'd use one of these. It is almost as good and much less expensive.
That will work too, but the plumber in me, well...you know :wink:

If you use what Jason suggested, you still need to use the teflon pipe dope, clamps, and heat the poly. This just eliminates the brass and the extra adaptor, and it is a touch cheaper.
 

kristof

Active member
Jun 8, 2009
37
Pittsburgh, PA
bk406 said:
poly looks 1 1/2 inch, is it?
The outer diameter of the black poly pipe is 1.84 to 1.87 inches which I think makes it 1.5" poly. I'm assuming poly pipe is sized similarly to NPS/IPS.

bk406 said:
put 2 CC clamps on the poly
Are "CC clamps" just regular old plumbing grade hose clamps?

Thanks guys. That procedure make sense. I was hoping for a solution involving glue or epoxy or something. Barb fittings with hose clamps make me nervous. I have a bunch of them underground anyway so I'll have to deal... :)

To clarify I need:
  • one brass/stainless/nylon adapter that's 1.5" male NPT to 1.5" barbed[/*:m:3dw0sthe]
  • two stainless hose clamps[/*:m:3dw0sthe]
  • one pvc fitting that's 1.5" female NPT to 1.5" slip[/*:m:3dw0sthe]
  • teflon pipe dope (Oakley's Great White???)[/*:m:3dw0sthe]

OR


Is the white 1.5" barbed to 1.5" slip pvc fitting something a pool shop might have in stock?
 

bk406

Well-known member
Dec 3, 2009
2,690
Central Massachusetts
Yea, you want the slip.

Hose clamps yes. As long as you heat the poly for a second, and use the teflon pipe dope,your good to go.

Dont worry about the mechanical fittings. You fix it like I told you, it will hold. See, all this glue and PVC are relatively new fangled stuff. It's good, dont get me wrong. I've used it and run a million miles of it. But, you have to realize that there are billions of miles (well, maybe not billions) of cast iron soil pipe thats been in the ground for decades that use nothing but mechanical fittings. When PVC and glue came out, you couldnt run it underground back then. It will leak, was the mantra. Now, you know what people who know only PVC say about mechanical fittings? "IT WILL LEAK" :mrgreen: Also, PEX water pipe is almost industry standard now. Sweat and solder copper? Whats that? :wink:
 

kristof

Active member
Jun 8, 2009
37
Pittsburgh, PA
bk406 said:
Yea, you want the slip.

Hose clamps yes. As long as you heat the poly for a second, and use the teflon pipe dope,your good to go.

Dont worry about the mechanical fittings. You fix it like I told you, it will hold. See, all this glue and PVC are relatively new fangled stuff. It's good, dont get me wrong. I've used it and run a million miles of it. But, you have to realize that there are billions of miles (well, maybe not billions) of cast iron soil pipe thats been in the ground for decades that use nothing but mechanical fittings. When PVC and glue came out, you couldnt run it underground back then. It will leak, was the mantra. Now, you know what people who know only PVC say about mechanical fittings? "IT WILL LEAK" :mrgreen: Also, PEX water pipe is almost industry standard now. Sweat and solder copper? Whats that? :wink:
Yea, I know.... What can I say? I like my welded connections. :-D

I'll see if I can source a stainless barb to mnpt locally. If not I may go with gray pvc. I found that mcmaster-carr has them. http://www.mcmaster.com/#48315k95/=7oghnz Of course they do. Mcmaster has everything!
 

Ohm_Boy

TFP Expert
May 1, 2007
1,344
Orlando, FL
I really don't like to have brass or even stainless on chlorine piping. It's not usually a good long-term scenario. PVC is pretty impervious. Oh yeah, AFIK, PEX is not approved or recommended for pool use.

Just my pair o' cents.
 

bk406

Well-known member
Dec 3, 2009
2,690
Central Massachusetts
Ohm_Boy said:
Oh yeah, AFIK, PEX is not approved or recommended for pool use.

.
Yea, i know, just using it as an example of mechanical joints.
Stainless, yea, probably wouldnt use it, good point. Not sure I agree on not using the brass, but nylon or PVC for this application would probably work just fine.
 

waste

TFP Expert
LifeTime Supporter
Mar 29, 2007
4,160
Coastalish 'down easter'
Kristof, sorry for coming late to this party :oops:

In your linked post you said there were elbows below the ground - are they the same heavy gray elbows used above ground? If they are the cheap thin white elbows, remove them can run the PVC from there! :hammer:

If you need any help with either glued or mechanical connections - simply ask of us :)