Moen Posi-Temp Shower Handle removal

it may have build up from water and soap on white viniger will clean all the hard ater build up off in order to tiurn it

Try removing the screw in center, and pull handle off. Check to see if maybe just inside of handle is stripped, or if it has a plastic insert with splines that are stripped. Thus just replace handle or insert or both. You can try turning it with vise grips or pliers carefully when handle off to see if tap itself is still good. My guess is a replacement handle and/or insert and you'll probably be good to go. Any hardware store should stock parts, reasonably priced.

Remove the handle and see if it will turn off without the handle and if it will reposition the handle alignment and your good to go. If no the cartridge will need to be replaced.

If it's the one I'm thinking of, remove cap in center, and remove Philips screw, and pull handle off. If you have the hex shaped piece still on the stem, look at underside for an Allen key, set screw and tighten it, and put handle back on.

On the underside of the handle there will be a set screw, usually an allen key that will need to be loosened. Once you do this the handle will pull right off. The moen website shows an exploded .pdf view. I found your model by searching with the model name, Legend. http://www.moen.ca/shared/pdf/l3175pt.pdf

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.

try 1/8

If your Posi-Temp has no water coming through the valve my first step would to replace the cartridge (Moen pn 1222). The valve as a simple one. Get the part first so you can ues the plastic tool that comes with it if you need to. Beneath the actual lever insert on the handle hub you will notice a small hole. this is to gain access to the allen head screw which holds the handle in place

remove the handle and there should be a white plastic deal behind the handle that you can remove it's a temperature limit setter so people dont burn themselves remove it and you will get the full hot water

heat it up with a torch, or just break it off, you can call moen at that point and kindly tell them that your handle broke and you need a new handle and cartridge. or you can get a drill and drill the allen screw out, they are such a pain i usually break them when i can get them out and get parts for it then