Fixing a water pipe drip in the wall behind the bathroom sink

[69GTX]

Was looking for some simple and effective fixes for a hard to get at hot water line drip at a union.....in the bathroom wall.
The horizontal union is connected to the back of the sink isolation valve. There could be other leaks on those old fittings that
aren't currently visible. The 1/2" pipe jogs to the side several inches before coming out into the valve. .

Piping installed in 1960. The sink cabinet makes it difficult to get in there. And I'd prefer not to take the sink and cabinet off the wall.
Access to the pipe is the hard part as it sits between a pair of 2x10 horizontal floor beams.....with only 4 inches of space inside the wall.
I've already gone through the back of the sink cabinet, tiles, and sheet rock to see the vertical pipe run that has to be removed.

I can cut most of the vertical run out and then try to attach something new. Copper pipe or Pex. I don't think there's enough flex in Pex to bend it out of the wall and into the under-sink area. If I went copper I'd have to get a right angle fitting on it inside the wall - either soldered or hydraulic crimp. Not really enough space for me to solder on a right angle piece as it's right next to the sink's 2" drain line on one side, and a 2x4 vertical support beam on the other side. Only realistic way to do that is to cut a much larger hole in the floor to push up a pre-made piece with right angle already on it. From there I could either shark bite a fitting on or try to solder on more copper pipe. A totally different thought might be to move the sink isolation valve down under the floor and run up a 3 ft long under-sink flex hose through the wall and up into the sink.

Ultimately, the entire bathroom needs to be re-plumbed (2 shower lines, 2 sink lines, 1 toilet line). So once I get the hot water line sink leak done, will probably replace the tub hw and cw copper pipes leading up into some new isolation valves.

Thanks for any opinions or comments.

69 GTX.

 

[facility1]

try cutting out hot water line,use half inch compression fittings,and stub to a threaded valve where clearence allows also chech the packing nut gland on valve,remove round handle off valve to get to as it maybe leaking

 

[69GTX]

try cutting out hot water line,use half inch compression fittings,and stub to a threaded valve where clearence allows also chech the packing nut gland on valve,remove round handle off valve to get to as it maybe leaking

Thanks. Had not thought of that option. As long as that's a good section of copper pipe on that final horizontal run into the
valve couplings, it should work. Might be a bit of work to break apart the old valve + fittings. I would put a new valve in place if
that all came apart cleanly.

 

[dnewton3]

Though I have not used them, what about "Shark Bite" type fittings? I believe they are available for copper applications; no sweating of copper in cramped areas. The only advantage here over compression fittings is that compression fittings often can be hard to install; limited space for tools to tighten the compression nut. The "Shark Bite" is just a press-on application. Shark Bite being a brand name; there are other brands of these type fittings available.

I prefer Pex, but in this case, if the SB fittings are available, it may make the easiest fix.

If you want to do Pex, you can "pre-build" the bulk of the required fix on a workbench, and then have only the last connection (make it low and easy to get to) where the crimp can be done easily. I agree that I would not bend the 1/2" Pex that tight; use a 90-deg fitting.

Either way, take this opportunity to replace any/all old valves.

 

[andyd]

Thanks. Had not thought of that option. As long as that's a good section of copper pipe on that final horizontal run into the
valve couplings, it should work. Might be a bit of work to break apart the old valve + fittings. I would put a new valve in place if
that all came apart cleanly.

I don't use compression fittings anymore. Being old school, I learned how to solder and used copper for supply lines . I would undo the trap to get some room and then if I couldn't replace the shut off in situ, I would solder the new one to a piece of copper and make the connection at a more convenient spot. Whichever way you go,please post a follow up

 

[JTK]

If you are re-doing the room at some point anyways, I would cut that copper in an area where you have room and use a sharkbite coupler, coupler with valve or even one with a flex line on it and adapt that to your sink.

I'd get all that plastic out of the way so you can work. Is that crumpled up blue thing a rag in there?

 

[tnt_motorsports]

FWIW I prefer these fittings from Menards over Shark Bite. I like they come with a locking ring and can transition from Copper to PEX. I have done some plumbing remodeling with these and had very good success.

Watts® AquaLock™ 1/2" Push to Connect Lead-Free Brass Coupling

This 1/2 inch CTS AquaLock? brass coupling works with copper, CPVC, PEX, LPDE, MPDE, HDPE and polybutylene tubing. It is easy to install, no tools or tube inserts are required. The fitting can be used for hot and cold water applications. The unique O-ring guide feature provides a zero-leak...

www.menards.com

Just my $0.02

 

[69GTX]

I'd get all that plastic out of the way so you can work. Is that crumpled up blue thing a rag in there?

Yeah, that crumpled thing is a old hand towel to collect any residual drip when we put the hot water in
service for a couple times each day.

Thanks for all the tips so far. Will probably get a better look at that valve and see what's behind it. If that rag
is picking up moisture several inches to the right of the valve.....it could be a pair of drips.

 

[andrew_j]

Legit plumber would tie in with copper.

 

[andyd]

Oh yeah, if you replace the shut off, take the plastic knob off before applying heat. AMHIK

 

[Rand]

I would rig it up with sharkbite or flex line or something
maybe put the bore cam up there to see the leak.
why would copper pipe leak?

What exactly is the water isolation valve.. just the shutoff at the faucet?

 

[someonesomewhere]

FWIW I prefer these fittings from Menards over Shark Bite. I like they come with a locking ring and can transition from Copper to PEX. I have done some plumbing remodeling with these and had very good success.

Watts® AquaLock™ 1/2" Push to Connect Lead-Free Brass Coupling

This 1/2 inch CTS AquaLock? brass coupling works with copper, CPVC, PEX, LPDE, MPDE, HDPE and polybutylene tubing. It is easy to install, no tools or tube inserts are required. The fitting can be used for hot and cold water applications. The unique O-ring guide feature provides a zero-leak...

www.menards.com

Just my $0.02

SharkBite fittings can do CPVC, PVC, copper, and PEX. Currently have some doing copper to CPVC connection duty under my laundry room on the washer supply lines. Been 5 years+ with no drips.

 

[tnt_motorsports]

SharkBite fittings can do CPVC, PVC, copper, and PEX. Currently have some doing copper to CPVC connection duty under my laundry room on the washer supply lines. Been 5 years+ with no drips.

Yep they do

Just my $0.02