Moen shower head manual - Moen Home

SOURCE: moen shower head leak

Single handle shower controls always have some water trapped inside. It has probably freeze damaged the cartridge

SOURCE: Moen shower head drips. Single lever shower only.

Probably need to remove and replace the cartridge. Often sediment will tear part of the o-ring or seal on the cartridge and cause this problem...
varies by model, but generally, remove the cap on the knob, unscrew the knob, remove the keyed sleeve, remove the round trim plate & shut off the service stops (verify they are fully closed by pulling out on the valve stem) next remove the retaining clip (needle nose and be gentle) that holds the cartridge in place, then pull the cartridge straight out with vice grips or similar (or get a puller). clean the cartridge, flush out the valve body by slightly opening both service stops, reinstall cartridge and clip, open service stops and see if it still leaks. if it does, take your cartridge to the store (any reasonable HW or plumbing store should have a replacement) and get a new one. then reverse the process to reinstall.
If you send me the model I'll get you more specific instrucitons and pictures...

SOURCE: Removing flow restrictor from Moen Brantford posi-temp shower he

How I remove them is take a drywall screw and screw in to the flow restrictor. Then grab it with a pair of pliers and pull out.

SOURCE: leaking shower/tub faucet, looking for replacement

Call Moen directly. They will ship what you need to your door, for free.

SOURCE: I have a Moen single handle tub/shower faucet. I

Your problem is in the water restrictor located inside the shower head. All plumbing manufacturers install these small plastic internal blockers to reduce water down to 2.5 gals per minute. In your case, this restrictor is most likely filled with sediment which is restricting it even further. Remove the shower head from the curved shower pipe. Look inside where the water goes through it. You should be able to see the restrictor. Maybe you can flush out the sediment. Otherwise, remove it and I'm sure you'll get more pressure then originally installed. Because most restrictors are sort of plastic screens or cones, I usually put a wood screw through the center of this product and then once a few threads bite in, I use a plyers on the head or the screw and pull outward while holding the shower head in a stable position. If you are able to get it out, technically your "out of code" because now your going to get all the water it can really supply.Most people are delighted to have it gone.
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