Delta R2707-PX, Help installing new roman tub faucet valves

[Lvrpl]

I've got to put a new roman tub faucet in our master and was hoping for some advice. I'm trying to avoid soldering/sweating as I don't do it nearly enough to be reliable. To that end, I'd like to use PEX if it's a viable option. I intend to use a Delta faucet.

The current valve that's being replaced is hard piped straight to the valves (and there also aren't shut-off valves on the hot and cold copper lines coming in under the tub deck).

Any reason I couldn't/shouldn't put a valve on the hot and cold copper inlet pipes that are a compression connection, and have a PEX outlet (something like this)?

And then from there, I'd just just the PEX version of the Delta rough-in valve that goes with our faucet (as seen here).

• Uses PEX crimp ring type connections

Any reason this shouldn't or couldn't be done this way? Thanks for any help, I'm obviously new to this.

 

[Terry]

The rough valve you're looking at is for PEX that is crimped. The shutoff you show is compression and the wrong size.
If you're going with crimp PEX, consider that for the shutoffs too.

The R2707-PX is for crimp PEX and the MF is expansion PEX.

 

[Sponsor]

 

[Terry]

I don't have the crimp tools, but I do have the expansion tools. An install with my tools would look like this.

 

[Lvrpl]

Ah, thanks, I totally missed that that valve had the wrong type of PEX barb.

So something like this valve should work with the rough-in valve I linked, right? (Assuming my copper supply lines are 3/8" - I'll double check that.)

Thanks for the help!

 

[Terry]

How about a picture of the copper you're connecting to. Most of that will be 1/2", 5/8" OD

 

[Lvrpl]

Sure. I hadn't looked closely at the supply lines yet, so could definitely be wrong on the 3/8". Figured I'd get the overall setup and valve types figured out and then double check sizes before ordering (although I do know that the PEX on the rough-in valve is all 1/2" from looking at those instructions).

Let me know if there's anything you see or other advice you might have. Thanks again.

 

[Terry]

You have 1/2" copper pipe.

 

[Lvrpl]

You have 1/2" copper pipe.

Ah, got it - thanks so much for the help!

 

[Lvrpl]

You have 1/2" copper pipe.

I'm having trouble finding a stop valve that has 1/2" compression (to attach to the 1/2" copper pipe) x 1/2" PEX...

It looks like sometimes people attach PEX via a compression fitting? Would that be a bad idea (and then I'd could get a 1/2" compression x 1/2" compression stop valve)?

Or maybe a 1/2" compression x 1/2" FIP stop valve, and then thread in a 1/2" PEX compression nipple into the FIP side?

Or something else?

 

[Terry]

Some of the sharkbite ball valves come with inserts especially for PEX

Or a ball valve with 1/2" threads and then adapt anyway you want.
Or a sweat valve and same thing.

 

[Lvrpl]

Some of the sharkbite ball valves come with inserts especially for PEX

Or a ball valve with 1/2" threads and then adapt anyway you want.
Or a sweat valve and same thing.

Ah, thanks. Ya maybe Sharkbite is the easiest way to go. Would you have any hesitation using it for say, 2 years, under a tub deck like this, for a pex-to-copper connection? (I say two years because we are planning to completely remodel the entire bathroom in the next 1-2 years.)