How to increase water pressure on wall mounted shower

SOURCE: Moen Bath Tub Faucet

Hi varn4620,

I'm Harvey the Master Plumber.

Your question is: You had to replace the faucet in the tub due to a broken plastic piece in valve stem. Bought a Moen ripped the wall out and put new faucet in. Went good untill we turned the water on and the shower rained on us. Tightened everything you could find to tighten .Every time the water is turned on the shower rains. Can this be fixed or is the faucet broken?

Is this new faudet a single handle? If so I"ve had this experience also. Most of the time it's because the guts were not lined up properly at the factory. You may have to play with it a bit.
Turn off the water and take the handle off and remove the sleave, remove and rotate the guts. Try 90' at a time. Turn water on to try it. Useually one of the other 3 positions will be right. The correct position is there, but it may take time to find it.

Feel free contact me again!
Please give me a rating here at fixya before you sign off
Thank you,
Harvey your Master Plumber

SOURCE: Not enough hot water

Some higher end models do have an adjustment that is behind the face plate. You would have to remove the handle and the screws in the faceplate to expose them. If you have adjustments they will be located on the brass valve body facing you. You will need a flashlight and a flathead screwdriver to make the adjustment. If your model is not equipped with adjustments you could have a faulty valve stem. The stem is comprised of a rubber band like gasket that separates port holes into which the waters flow. There could be some piece of trash blocking the port not allowing adequate water from the hot side into the valve.Some valves stems are also able to be installed upside down causing the same issue as the ports do not rotate fully to allow adequate supply. However you say that you have adequate pressure on the hot side but not warm enough. There is another possibility also based on the way the shower supply was plumbed but there is no need to go into this unless this does not resolve your issue. I hope this is of assistance and thanks for using Fix Ya. Please let me know if I can be of further assistance.

SOURCE: moen single handle valve tub/shower

The Moen Posi-Temp Valve is a pressure balanced valve and when not used for long periods of time they can stick causing only cold or hot water to pass through the valve.
A New Posi-temp cartridges can be purchased at most plumbing supply houses or big box outlets such as Lowes or Home Depot.
As long as you had cold water before, a new cartridge will solve the problem. In the future it would be wise to occassionally operate the valve at least a couple of times a month in order to keep the pressure assembly from becoming lodged in position. Just follow the instructions included with the new cartridge on the proper removal of the old cartridge and the installation of the new cartridge. a little silicone grease inside of the valve before installing the new cartridge will also help.
Be sure that there is no particles of the old cartridge left in the valve.
sanray

SOURCE: Moen posi-temp valve with little pressure

I have the same problem. Anyone know how to fix this?

SOURCE: No hot water pressure on kohler bath / shower faucet

Try draining the system and apply air pressure (min 30psi) to each faucet. Open other hot water faucets to allow pressure to vent. Next try draining and cleaning the hot water tank.