I have a 19 266 Thermostat trim Shower/Safety valves shower. The valve is broke inside. It just turns with no change in temp. I removed the handle but can't remove the valve. Help.

http://youtu.be/CxM3j8bwmNE

just turn the water valve down some

Moen cartridges require a Moen puller tool. Your local hardware store will carry this. You may not be getting hot water because there's a safety tab located on the cartridge that is preset during initial installation as an anti-scalding safety feature, and that may have worn, broke, or have shifted during time. Hope this helps!

You will need to remove the old cartridge from inside the shower valve body and either refurbish it with new rubber seals and O rings or replace the cartridge altogether (preferable). It's not a complicated fix but the Posi Temp cartridge can be a bear to remove. Moen and Danco make special 'pullers' to make the cartridge removal go a little easier (sold at Lowes/HD and plumbing supply for anywhere between $15 and $35 but well worth it, IMO).

You can cap the lines at the tub faucet to rule out tub faucet. It maybe mixing there.

Faucet may be bad also the safety stop will alow you to change water temp it can be tricky to adjust water temp.

Remove the handle and turn the stem of the cartridge 180 degrees then put your handle back on.

Pull the trim off of the valve and you will see a 1 inch diameter flat screw, unscrew that and clean it out and try it again. If rinsing it doesn't work you may need to replace it. It is called a balancing caulk.

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

You have to remove cartridge and rotate 180 degrees then re-install. Was it removed or replace lately?

pull the holding clip and then pull the valve out. you might have to grab it with channel locks or pliers because sometimes they are hard to pull out