Master Bath Supply Line Runs

[MTy]

I'm nearly finished with my DWV and will be starting on the supplies this weekend. I'll be using Uponor PEX A. A couple of prelim questions.

1. The two supplies for the single vanity run under the floor and then a short distance up the wall. I was going to cut the copper under the floor as close to the wall as possible and still run the double vanity lines. However, I noticed that in one spot the copper has oxidized a good bit. Is this an issue? I start my PEX runs before those spots.

2. It looks like there was a leak in the 3/4 cold water line at some point and a repair was made from the back vanity using a shark bit. I suspect the tight quarters was the reason. Is this something I should repair with a sweat joint? I've not sweated copper before (will be learning and practicing) so trying to do as little as I have too. Plus this seems pretty close to the wood as well for sweating. Can it be left as is?

 

[Reach4]

It looks like there was a leak in the 3/4 cold water line at some point and a repair was made from the back vanity using a shark bit. I suspect the tight quarters was the reason. Is this something I should repair with a sweat joint? I've not sweated copper before (will be learning and practicing) so trying to do as little as I have too. Plus this seems pretty close to the wood as well for sweating. Can it be left as is?

I think you are saying there is no leak. You can leave the SharkBite in place.

 

[Sponsor]

 

[Jeff H Young]

some work was done on the 3/4 you can tell the copper on bottom looks clean (newer) . shark bites fairly reliable I'm not crazy about them but then again solder joints can fail too so it looks solid. if the tarnished 1/2 inch is questionable and especially type m (got the red markings on it ) then cut it off and run your PEX a little further
.

 

[MTy]

I've done some practice soldering in perpetration for today. I've tested the joints under pressure by soldering on a hose fitting, no leaks. Further, the solder has even coverage when I pull the fittings apart. So I think I am good to go. The only issue I have is I can't seem to keep the copper from discoloring a bit, which I understand means I am getting it a bit too hot.

Is this a big issue? FWIW the second the solder starts flowing I am removing the flame. I am using mapp gas, lead free solder, and Nokorode Aquaflux, if that make any difference.

Second Q- Once I solder on the pex a adapters my plan was to cut small pieces of pex and put caps on them an then put them on my adapters so I can test my copper joints before running all of my pex. Would the be any issues removing the pex a "stubs" from the adapters after testing so I can do my runs? I figure I can just cut the pex off fairly easily.

 

[Reach4]

Would the be any issues removing the pex a "stubs" from the adapters after testing so I can do my runs? I figure I can just cut the pex off fairly easily.

It's not that easy IMO. When I did it, I clamped single edge razor blades into a locking pliers to provide a cutting depth stop. For testing with easier removal, you could forgo the normal ring, and clamp the pipe around the fitting with a worm gear clamp.

What is the purpose of your proposed test -- checking to see if your solder joint is waterproof? I really can't see you having a leak on your soldering that could leak water. If this is a self-mandated test, I think you are being overly cautious.

 

[Jeff H Young]

The only failed solder joints I’ve seen in almost 40 years of being a repair service plumber are a result of poor quality workmanship.

A properly made solder joint is stronger than the pipe wall itself.

Agree horribly soldered joints suck are worse than a well installed shark bite . but I don't recommend either. well installed PEX , CPVC , or galvie aren't my preferred methods either. but I have and will continue to work with all of them when appropriate.
Unless its real easy to get to and where damage will not likely occur , covered up piping I expect 30 years life left to safely recommend covering shark bites don't really fit that to me. but If a guy cant solder and willing to take some risk so be it. but of course I don't recommend leaving 50 year old questionable copper piping either. So hell yea repipe in type l copper with a top notch plumber would be good if pockets are deep and your a quality oriented person. but not a single answer for all cases and homeowner is the boss.

 

[MTy]

It may have been a self imposed thing but I am glad I did it. One of my joints leaked. Got that fixed though. Cut out the entire section and redid it. No leaks! I have one of the razor blade cutters. Takes some time but not too hard to get the pex stubs off.

On another note. I have the Delta R22000-WS shower valve. I am supposed to cap one of the valves because I am using the 3 function diverter. It comes with a little brass cap that slides in but no threads. I take it this is supposed to be soldered in? Or do I buy a cap to thread over it?

 

[Jeff H Young]

either way I use the sweat plug but a brass cap is ok to use

 

[MTy]

So when I demoed the bathroom the compression fitting started leaking. When I pulled it off I noted the pipe was in really bad shape so I cut it back just a bit and installed a new compression fitting.

At the time I thought I was moving the toilet so the new fitting was supposed to be temporary. However, I am not moving the toilet now and the stub is not long enough the the fitting and drywall. Not a big deal to sweat and new stub since the copper T is right there.

But do I need to be concerned about weakening the other joints in the T when I go to pull out and resolder a new piece of copper in? Should I cut further back from the T and replace the whole section including T? Its 40 year old type M copper and I'll be suing type L, if that makes a difference.

 

[MTy]

Bump on this. Probably going to replace the entire T but its a tight space with other old joints nearby. Do I need to worry about weakening old joints when soldering a single new piece in?

 

[Reach4]

Bump on this. Probably going to replace the entire T but its a tight space with other old joints nearby. Do I need to worry about weakening old joints when soldering a single new piece in?

Even if you told me how far away the old joints are from the new soldering, I would not be able to answer that. But somebody else might be able to do that. I know keeping the old joint damp can keep that joint cooler.