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 Shower/Tub valves with PEX tubing
Author: sum (FL)

I have always read that when using PEX tubing, specifically the crimp ring version (not the cold expansion PEX A fittings), due to the restriction of the crimp fittings, that one should not run PEX on the outlet of a shower/tub valve to the tub spout. Reason being the restriction is such that there may be enough back pressure to cause water to come out of the shower.

However, I came across some valves, for example this MOEN U361X, which is NOT a mixing valve but a multi port diverter valve. It has all the inlets and outlets in 1/2" crimp PEX connections.



Here are my questions.

(1) The inlet is a 1/2" crimp PEX connection. So the mixed water is already restricted coming in. Yet it has a three port outlet capable of supporting three devices independently or at the same time. I am having a hard time imagining how it can have enough volume to have a hand shower, a rain shower head and an overhead wall shower head all going at the same time.

(2) The specifications/instructions showed how to install for 2 or 3 devices. It is installed on top of the mixing valve so no tub spout. Can a tub spout be used in this case? Can someone take a side outlet, and run it across, down and back over to run a tub spout? Or can someone install this below the mixing valve and turn this diverter upside down to go down to a tub spout?

I am not planning on using it, I am just curious when I saw this.



Edited 1 times.

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 Re: Shower/Tub valves with PEX tubing
Author: packy (MA)

funny but all the installation instructions of find are for a different valve body. 1/2 FIPS with the opening reamed out so 1/2 copper fits inside.

this is a good question for moen engineers.

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 Re: Shower/Tub valves with PEX tubing
Author: hj (AZ)

It is a transfer valve so all the instructions about full size piping do not apply. It shuts off ALL the openings not being used, so back pressure is not a problem.

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 Re: Shower/Tub valves with PEX tubing
Author: bernabeu (SC)

hj is correct

(gasp ... choke ... gaaaaa ... )


apparently it is used as part of / along with Moen's 'new' M-Core 'mixer valve'


[www.bing.com]

and see the video [www.amazon.com]

- - - -

Retired U.A. Local 1 & 638
"Measure Twice & Cut Once"

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 Re: Shower/Tub valves with PEX tubing
Author: hj (AZ)

Gee, I hope you survuved that episode. Hopefully, it will be the last one, since I do not think you could survive two of them.

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 Re: Shower/Tub valves with PEX tubing
Author: bernabeu (SC)

...... glad to be of amusing service ......

smiling smiley

- - - -

Retired U.A. Local 1 & 638
"Measure Twice & Cut Once"

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