Tub Spout with ProPEX won't work.

[CCCBuilder]

I have heard that the tub spout can be done if using PEX-A that has the full size diameter since the PEX expands OVER the fitting and doesn't crimp down to a smaller size. If my shower/tub mixer valve has 1/2" threaded male fittings for all the lines, could I use 1/2" PEX with a 1/2" drop ear for the tub spout? Would looking for a 1/2" FPT x 3/4" ProPEX fitting be better so 3/4" pex can run down to the Drop Ear Elbow? I don't know if they make a ProPEX 3/4" x 1/2" FPT drop ear elbow for the spout though.

I know that copper is preferred, but if I do not have the tools to work with copper, I was hoping this ProPEX may be fine. I assume that if the shower/tub mixer valve had a 1/2" FEMALE threaded outlet for the spout, then I probably would be a bit too restricted right there using a 1/2" MPT x 1/2" ProPEX fitting.

Please let me know if you've seen it done, and seen it work fine without the shower rise phenomenon.

 

[Terry]

PEX has never worked for a tub spout.
The OD is the same as copper, but because of the thicker wall, it's a smaller interior dimension. Also the fittings further reduce the flow.
Using PEX to run to a tub spout forces water up to the shower head while filling the tub. All instructions mention this.

 

[Sponsor]

 

[Plumber69]

I think you can use 3/4" PEX, not sure... never have.

 

[Terry]

I think you can use 3/4" PEX, not sure... never have.

Once you've restricted for the 1/2" side of the fitting, I don't think so.
After you've tiled up and it's in the wall, it's too late to change it. I even had a showroom try to tell me it didn't matter. I guess they didn't like reading instructions. We plumbers need to though. I was the second plumber on the job making the correction. I removed the PEX and fittings, changed it out to copper and fixed it. We had to open up the wall behind it to make the changes.

 

[Reach4]

They sell a 3/4 in. PEX Barb x 1/2 in. MIP Brass Adapter Fitting for crimp/clamp attachment, but I don't find one in F1960.

You can use PEX-A pipe with crimp/clamp fittings, however. You could use an F1960 drop ear elbow on the other end of the 3/4 PEX-A.

 

[Plumber69]

Brass nipples and couplings, problem solved

 

[Terry]

Brass nipples and couplings, problem solved

Brass nipples with couplings would work. Anything that maintains the sizing and with no restrictions.

 

[Dprocket]

Glad I came across this thread. I've removed my shower-only and am in the process of replacing it with a shower/tub combo.

The existing supply to the old shower was 1/2" gray polybuteline pipe that transitions to copper just before it reached the valve in the shower. I was planning to transition from the polybuteline to PEX under the floor and run that up to the new tub/shower combo, but it sounds like I need to rethink that plan. How should I proceed?

 

[Terry]

Running PEX to the valve is fine. You can't have PEX to a tub spout.
The pipe that leads to the tub spout needs to be full size without restrictions or it will push water up to the shower head.

 

[Plumber69]

Pressure in my town varies, im running 3/4 pex to all tubs now

 

[Dprocket]

I

Pressure in my town varies, im running 3/4 pex to all tubs now

Don't think running 3/4 pex would work for me, since I'm transitioning from 1/2" polybutaline... Right?

 

[James Henry]

If I were you I would find someone to solder up your shower riser and your tub spout. theirs more than one reason to have both piped in copper.
the copper shower riser helps keep the shower stub out rigid when people are adjusting the shower head and the copper spout stub out for the spout is good to have in case someone slips in the tub and the first thing they grab for is the spout. just my opinion.

 

[Dprocket]

Is it possible to go: existing 1/2" polybutaline > 3/4" Pex > 1/2" copper
or should I go:
existing 1/2" polybutaline > 1/2" Pex > 1/2" copper

Note, the polybutaline won't reach to where the new spout will be. I also, plan to use sharkbites to connect the butaline to the PEX.

 

[Reach4]

Is it possible to go: existing 1/2" polybutaline > 3/4" Pex > 1/2" copper
or should I go:
existing 1/2" polybutaline > 1/2" Pex > 1/2" copper

Note, the polybutaline won't reach to where the new spout will be. I also, plan to use sharkbites to connect the butaline to the PEX.

The objection to PEX on this thread is only between the valve and the spigot. I am pretty sure that you have never considered having polybutaline between the valve and the spigot.

If you wanted all F1960 PEX to avoid working with copper, this should overcome objections -- other than soldering copper is actually easier:

 

[Terry]

ANY restriction from the valve to the spout pushes water up to the shower head.
Once it's installed there is no way to fix it without tearing things out.

 

[Reach4]

I think any restriction from the tee to the spout pushes water up the to the showerhead, but restriction before the tee will not.

 

[Terry]

The 1/2" side of the PEX fitting is a restriction. But go ahead, it's been tried before and it's failed. Let's put lots of stories of failed work here.
Removing tile and wall board to make repairs is fun.

 

[Dprocket]

Sorry folks, I think I'm derailing things here by not being clear. The above graphics and instructions are clear that I should not use anything other than copper between the valve and spout.

The polybutaline is about 5' under the floor that goes into the bathroom. At that point, I plan to transition from the 1/2" butaline to PEX and then run PEX up to the copper. From copper, I'll go into the valve.

My concern is the 1/2" butaline going to 1/2" PEX is reducing my throughput as the 1/2" PEX is actually a little less flow (correct, on that?).

I'm 100% OK with running with copper when the PEX comes through the floor up to the Valve and and then to the spout/shower.

 

[Terry]

It's not an issue running PEX or PB to the valve.