Moen Single Handle Shower/Tub valve problem

short.circuit · Apr 13, 2009

I installed this valve on a friends tub/shower in her basement.

http://www.moen.com/shared/pdf/82910pt.pdf

when we turn the hot water on, it comes out the spout just fine.
if we turn some cold on with it, some water comes out of the shower.
should we bug moen, about getting a replacement cartridge? or would that help?
thanks in advance for any advice...

here's a pic of the install...

Redwood · Apr 14, 2009

No because it was piped incorrectly.
Read carefully the instructions and you will see that you cannot run PEX to the tub spout.
The slightly smaller size ID of the PEX creates just enough back pressure to cause water to rise up to the showerhead...

Only copper or IPS pipe may be used here.

Sponsor · 2022-01-29T12:20:58-0800

Jimbo · Apr 14, 2009

Apparently you missed the step in the installation instructions where it said to use ONLY copper pipe, NOT pex or cpvc, for the spout drop.

short.circuit · Apr 15, 2009

fortunately it was a fiberglass, shower/tub surround. was able to remove the 1/2" male & dropear 90. i'm wondering if the pex pipe would work ok with sharkbite fittings. pex fittings look more restrictive. i was tempted, but went with copper & it works fine now. way more flow/pressure.
lesson learned... thx again

Jadnashua · Apr 16, 2009

You'd have had the same problem with PEX...the ID is smaller than copper.

hj · Apr 16, 2009

shower

HOW you connected the PEX would not have made any difference. The problem was the PEX itself.

Moen Single Handle Shower/Tub valve problem

short.circuit

New Member

Attachments

Redwood

Master Plumber

Sponsor

Paid Advertisement

Jimbo

Plumber

short.circuit

New Member

Jadnashua

Retired Defense Industry Engineer xxx

hj

Master Plumber

Similar threads