Re: Follow Up to Galvanized to CPVC or PEX
Posted by Terry Love on December 09, 2003 at 12:27:44:
In response to Re: Follow Up to Galvanized to CPVC or PEX
: 1. First, I need to dig down inside the crawlspace to where the galvanized supply line comes in under the house.

Okay

: 2. Where it turns 90 degrees to come up is where I will want to install a new fitting.

Yes, you do want to start from that point.

: 3. I will need to cut (I assume?) the current galvanized line after the 90 degree turn and then unscrew the pipe above the existing galvanized elbow. If I cannot budge the joint using a wrench, I should use a blowtorch to loosen the joint (I saw this info while researching a much earlier post on this board). I then remove the galvanized elbow as well.

Do not remove the 90 el, unless you are prepared to go farther. Anytime you put a pipe wrench to old galvanized pipe, you chance splitting or crushing it.
Leave the 90 el there for now, when the water service is replaced in the future, then you can replace it.
If you use a torch to loosen the fitting, remember that it only takes enough heat to expand the fitting. Keep the torch off the pipe.
You want the pipe to stay cool, or at least not as hot as the fitting.

: 4. After removing the old galvanized elbow, I install a new CPVC elbow with a fitting that can screw onto the outside of the galvanized supply line.

Here you screw a 6" long "brass" nipple into the old galvanized 90 el and into a IPS ball valve.

: 5. The fittings I saw at Home Depot can be solvent welded to the CPVC on one end and then have a screw-type adapter on other end that I assume is unscrewed, soldered to copper, and then screwed back in. Question - do I use Teflon tape or some sort of other sealer on the threaded connection? Also, I assume a "six inch nipple" is just a short piece of copper pipe? I know I may sound stupid, but I want to ask the dumb question to be safe.

Copper and brass are quite different.
It would be a brass pipe nipple.
You would not attach copper to galvanized.
All tapered threads need a pipe thread sealant, Either the paste or Teflon tape.

: 6.

: 7. Then I screw the brass nipple to an IPS ball valve that has screw type fitting. Another dumb question - what is an IPS ball valve? I found a 3/4 inch and a 1 inch copper stop and waste ball valve. Will that do the trick, or should I be looking for something else?

Gotta be either a ball valve, (my choice) or a gate valve, not a "stop and waste"

: 8. Then on the other end of the shut off valve, I screw in CPVC pipe with the proper fitting and then continue from there.

: Question - would it be a good idea to install a pressure regulator after the shut off valve? There is not currently anywhere in the system that I have found.

Only if you have more than 80 PSI.  
If you have more than 80 PSI and install a pressure regulator, then you will need to add an expansion tank.  

: So it looks like if I do all of that correctly, I can then pick up with the CPVC or PEX and work on replumbing the existing galvanized plumbing in the crawlspace.

: Any ideas on the chances of breaking the galvanized pipe when I attempt to unscrew it at the elbow? I will do my best to locate a plumber we can keep on standby in the event that happens.

Use two wrenches, one on the fitting, the other on the pipe, and don't remove the 90 el in the ground.


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