Shower manifold PEX or copper ?

[Hallowhead1]

Howdy,

I am running PEX to my bathroom and planning to into install PEX up to a bronze threaded fitting that will screw onto the manifold. Do you recommend using PEX or copper to run to the shower head and tub spout?

Best,
Joe

 

[Terry]

Instructions for all of the tub valves mention using copper to the tub spouts and absolutely no PEX, or while running the tub, it will push water upward to the showerhead and water will come out both places.
Running PEX to shower heads is fine.

MOEN

KOHLER

 

[Sponsor]

 

[Hallowhead1]

Thanks !

So to confirm I can run PEX to the manifold and PEX to the shower head but do NOT run PEX to the tub spout?

 

[wwhitney]

Your use of the word "manifold" is non-standard. What is the model and part number?

Normally it's called a shower valve, and it has just one output, which has a large diameter connection to the tub spout and a small diameter connection to the shower. That way water goes to the tub spout normally; and if you engage a diverter on the tub spout, blocking the tub outlet, water goes back up to the shower. Using PEX to the tub will cause a restriction that makes water come out of the shower head all the time, so you need copper to the tub spout.

If you have a shower valve with built-in diverter, with two or more actual outputs from the shower valve that you select among, then you should be able to use PEX to the tub spout if desired. These are rarer, so you probably have a typical shower valve with diverter on the tub spout.

I bring this up because your use of the word "manifold" suggests multiple possibly simultaneous outputs.

Cheers, Wayne

 

[Hallowhead1]

Your use of the word "manifold" is non-standard. What is the model and part number?

Normally it's called a shower valve, and it has just one output, which has a large diameter connection to the tub spout and a small diameter connection to the shower. That way water goes to the tub spout normally; and if you engage a diverter on the tub spout, blocking the tub outlet, water goes back up to the shower. Using PEX to the tub will cause a restriction that makes water come out of the shower head all the time, so you need copper to the tub spout.

If you have a shower valve with built-in diverter, with two or more actual outputs from the shower valve that you select among, then you should be able to use PEX to the tub spout if desired. These are rarer, so you probably have a typical shower valve with diverter on the tub spout.

I bring this up because your use of the word "manifold" suggests multiple possibly simultaneous outputs.

Cheers, Wayne

It's a Moen shower and tub system. I suppose it's a diverter. For peace of mind copper to the spout it is

 

[Terry]

It's a Moen shower and tub system. I suppose it's a diverter. For peace of mind copper to the spout it is

Do you have a part number for the Moen valve you're installing?

 

[Hallowhead1]

Do you have a part number for the Moen valve you're installing?

It's the MOEN U140CIS M Core 4 port 1/2"

 

[Terry]

It has the same instruction for using copper to the tub spout too.
PEX pushes the water upward, and it's a hassle breaking tile to fix it.