Whats the best way to connect an old galvanized water line to a new cpvc line.

[shooteneq1]

I have a demo ongoing in my house and need to replace the mixing valve for the shower. All the water lines are old galvanized pipes and I seriously doubt I can unscrew them from the original threads and attach new lines. What is the appropriate way to connect an old galvanized pipe to a new cpvc line? I know the whole house needs to have all the lines redone eventually and I plan to do that, but i need a fix to last the next year or so before I have that done. Thanks for any input even if it's bad news.

 

[shooteneq1]

Ok so after doing some research it appears there is no real code compliant or actual quality way to attach new piping to this without re threading it. So my next question would be is it possible to re thread this pipe in its current condition? The rust on the outside of this is mostly superficial due to a fresh leak onto it before I cut the water off.
I am not worried about the stud as close as it is as if I cant get a threader in there I will jst remove the stud, thread the pips, and install a new stud.

 

[jimmi]

I had a similar situation with a garage sink situation. I don't believe there is any way to work with a galvanized pipe except at a joint. Don't think it's possible to rethread galvanized, so you need to get to a joint that can be unscrewed. To my knowledge there is no type of pex or shark/gator bite fitting for this situation.
The good news is, that if you wd40 the crap out of a joint, it may unscrew a little easier than you'd expect. Good luck.

 

[shooteneq1]

Here is my problem. For whatever reason whoever originally put the plumbing in this house put elbows about 6" off the ground and they extend about 3/4" past my wall that needs to be tiled. So I have to move these back at least 3/4" so they are flush with my wall or ideally a bit farther back because as of right now I can't put my backerboard on the wall. Plus the mixing valve is still leaking all over. I have low hopes of getting those elbows off with the threading intact enough to put another new piece in there. SO on the chance that the threads all break and I cant get a new pipe in what do I do. I have pretty much zero hopes of a thread to grab if I need to do into the ground. Are you sure I can't clean these pipes off right below that first elbow off the ground and put a male threading on it?

 

[breplum]

Is that a slab on grade or is there a crawl space or basement?

 

[breplum]

A plumber with the right wrenches could unscrew to the last elbow,
If those are galvanized pipes coming out of a slab, I wouldn't touch anything b/c it is a terminal situation - end of life of the galv. pipes.

 

[shooteneq1]

They are coming out of a slab. I basically need a short term 6 month fix as after this bathroom is gutted the one on the opposite side will be. Then i will be replacing all the plumbing and routing a new water supply to that side of the house through the ceiling. but for now i need to make this work. Is it possible if the threads break on the elbow I could then just use a compression coupling to a new set of pipes?

 

[breplum]

If you use a compression coupling follow these precautions:

1. Keep the whole assembly accessible. Do not cover permanently.
2. Make sure that the static pressure to the building is under 80 psi. Add a PRV if not.
3. Securely brace the compression couplings and attached pipes with solid blocking and multiple tight pipe straps. Know that pressure will blow that thing off or push the pipes right out if not extremely well clamped.
4. Put wye strainers upstream of the old galv pipe heading to your fixture to prevent rust clots, because you are going to experience rust particle migration.

 

[shooteneq1]

I know the pressure in the house is nowhere close to 80 but I would need to go outside to verify, i want to say its at 30-60psi. And yes If i used one i planned on running a couple boards across and securely attaching them. I don't want to have to do it at all but its like the last ditch effort if the pipes crumble at the joint. he opposite side wall is tile and going to be demoed in about 4 months, I might go ahead and cut a section out and make a quick access panel just incase I do need to access them.

 

[shooteneq1]

Thanks for the help all, finally got around to doing this today. I had soaked the joints over a period of 3 days with a penetrating sealer and was able to get them off at the first elbow and much to my surprise the threading was still in great condition. I was able to put an adapter easily on from there to convert to cpvc to hold me over for 3 months until I gut the bathroom on the opposite side and wall and then have the whole house replumbed at that time.