SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

If it's a female union end of a manifold fitting, the usual fears of female plastic threads shouldn't apply. It will be the O-ring doing the actual sealing, and not the teflon tape you might apply to the threads.

Yes, there is a tendancy for metal MPT to FPT PVC threded junctions to leak. Biggest culprit is over zealous tightening, causing small cracks in the female PVC fitting. Then, added to the expansion and contraction caused by temperature changes, this is exacerbated and may lead to a leak.

So, I use only MPT PVC to FPT copper or brass.

Boots is a pro's pro. So if he want to reverse the above scenerio, I am confident he can without a leak.

I use 5 turns of teflon tape on every metal to Male PVC threaded adapter.

I like Brass better than copper. I like how heavy it is, and I can use a tool to help me tighten the joint. (Yes, I tend to overtighten a bit, and use a quarter to half turn past maximum hand tightness). Again, I use 5 turns of teflon tape.

I have used copper MPT to a brass FPT faucet or hose bib. I use teflon tape on these.

Hope trhat answers your questions.

And, Boots, I am in Leary Country.

Jeff

Quoted from "Wet_Boots"

You might use a 3/4 x 1 CxMPT adapter, although that might be more expensive.

I've read around on some other plumbing type forums that using a metal male thread into a plastic female thread is not recommended. Supposedly more likely to leak.

You might use a 3/4 x 1 CxMPT adapter, although that might be more expensive.

I'm working on a plan for putting a system in at my house and am trying to figure out the plumbing from the water supply to the valve manifold.

Basically I've plumbed from my water supply up and out of my house up through the PVB and then out to a hose bib and down below the ground with 3/4" copper. Now I need to connect to a dura 4 port swivel type manifold. My plan is to solder on a 3/4" copper elbow female adapter. Then use a pvc reducing nipple 1" x 3/4". The 3/4" end into the copper female adapter and the 1" end into the dura swivel manifold.

Is this the right way to do this? Should my female adapter be brass instead of copper? Do I need teflon on the PVC nipple into the female adapter (i don't think that I need it into the swivel manifold since it has an o-ring)? Is there a better way?

Thanks
wb