PEX supply line with copper stub outs

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Claraarcher

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Hi All,

I have a question related to using PEX pipe but connecting copper stub outs thru the walls so I can solder on speedy valves.

If I use the stub outs sold in stores that are maybe 6 inches through the wall and have a compression connector built in, can I solder on the valve after the inspection or will that, melt the PEX?

If I use a combination of PEX / coppers how long of a piece of copper should I use so that I can solder on valves after the sheetrock is installed without having to worry about melting or damaging the PEX to the point it leaks?

I find info on operating temperature of 180-200 degrees but that is not what i am worried about as it is residential use (not for heating) so temp is definitely under 180 degrees

Thanks!
 

James23912

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I’m don’t have much experience but I did 3 sinks and 3 toilets using the shark bite connectors onto the copper stub outs, easy for me and no problems, may cost more
 

Jeff H Young

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I think some where they sweat angle stops on but not in my world don't think I've ever seen them installed . therefore I would never give a second thought other than if someone gave them to me even then I probably wouldn't throw in trash but likely I'd never use them.
Compression stops 99.99 percent of time in copper.
I like Dahl stops too , don't care for the look but great quality. Brass craft is good too not good enough to some , but I've used them for decades.
 

Claraarcher

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hi all,

a follow up question or two but related the new valve for the tub.

I have a Danze Parma Treysta valve with IPS inlets / outlets. I am using copper adapters and wanted to know if

1. soldering the adapter that has Teflon tape is ok and won't compromise the tape? Can it take propane gas heat? (adapters are so I don't have to use MAP on the valve due to my noob soldering skills. easier to solder copper to copper then to brass for me :)

and,

I read somewhere that mixing PEX and copper pipe on a valve could lead to issues with the shower head and tub fill? if I recall right it sounded like the differences in the pipe means different pressures so water would come out the tub fill or shower head when using either function? so my question is:

2. my valve has a diverter on the valve so is this an issue even if I were to use PEX supply and to the shower head but copper stub out for tub?

Thanks!
 

Terry

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I think most of the plumbers here are installing Delta or Hansgrohe.
I can never find the right cartridge for the Danze/Gerber valves.

gerber-tub-shower-spout.jpg


This is from the Gerber TREYSTA® instructions.
You can try PEX to the spout, but you won't see me doing that.

I normally sweat the fittings on before threading onto the valve body. And then I tape and install after cooling.
If I ever solder to a valve, I remove the cartridge.

gerber-treysta-valve.jpg


gerber-tub-shower.jpg
 
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John Gayewski

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Generally you'd sweat your adapter onto piece of pipe and then cut it to the desired length. Then from there you'll be able to stay at lower temp on the threaded joint while you sweat the next fitting on. You can get a wet rag and put it on the threaded joint while you solder the adapter, but being that close will be hard to keep the threaded portion cool enough to safely keep the thread tape from melting. You could also try a lower temp solder like Bridgit.

No PEX on the tub spout. No reason to try it.

Yes PEX on the shower head riser it's fine, but copper is better in my opinion.
 

Claraarcher

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Hi Again,

I did copper pipe on the entire valve installation.

I have niche under the shower head as that was to only place i could install due to framing "issues" so the shower head feed pie is re-routed around the niche.

i turned the ear drop thing so that the inlet is 90 degrees to the left where the pipe now runs.

when i tested for leaks the chrome shower head arm that comes out the wall when tight is facing the ceiling (Lol of course it is :)

If i back it off i get a slow leak (used Teflon tape and pipe dope that say it is good on water pipes).

I seen videos where people use a socket wrench extender an get the pipe to be at the right angle.

Is this the only way? any other tips?

Thanks!
 

Claraarcher

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OK I was afraid to damage the threads that go into the shower head but sounds like getting an extra 1/2 turn should be doable.
 

John Gayewski

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ok i was afraid to damage the threads that go into the shower head but sounds like getting an extra 1/2 turn should be doable.
There's always a possibly of splitting the female 90 in the wall, but it should take an obvious amount of force to break it. I'm sure you could break one that had a defect pretty easily. But there should be a little space to see in there, with a cap on the shower arm, you could turn the water on and look for a drip, if you think something broke.
 
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