How to Install Moen Shower Valve

Moen offers consumers a simple cartridge system suitable for a wide variety of single-handle valve bodies used in bathroom sinks, kitchen sinks, tubs and showers. Despite having expensive cartridges, Moen’s system is worth the investment, as it lasts a very long time. The company also continues to make the same parts used in valve bodies that are 40 years old. This means finding replacement parts would not be a problem.

Installation and replacement are best done by professional plumbers, especially if you’re not confident with your handyman skills. But if you know you can handle it, go ahead.

How to Install a One-Handle Posi-Temp® Shower Valve: Pex to Pex

What is great about Moen Posi-Temp Valve is that it has both threaded and soldered connections, making it suitable for a wide range of plumbing, such as copper, IPS (galvanized steel), CPVC and PEX.

Tools You Will Need

  • Adjustable pliers
  • Adjustable wrench
  • Crimping tool
  • Caulk
  • Phillips screwdriver
  • PEX tube cutter
  • Plumber’s Putty
  • Safety Glasses
  • Tape measure
  • Thermometer
  • Thread seal tape
  • Torch and Lead-free solder kit

You may also need to buy plumbing parts, such as female threaded to PEX adapters, PEX and copper couplings, copper and PEX tubing and crimp rings.

Installation Steps

1. Shut off the main water valve, and locate your plumbing access panel. Ask your local plumber if you don’t know where to find them.

2. Attach the plaster ground, which will be positioned to your tub wall, to the shower valve. Make sure that the valve will be positioned 32 inches from the floor of the tub, to ensure proper operation.

3. Attached the new valve to the drop outlet going to your tub, using a half inch copper coupling.

4. Wrap the inlets and outlets of the valve with a thread seal tape wrapped around them in a clockwise direction. Then screw in a half-inch female threaded to PEX adapters, and then tighten using an adjustable wrench.

5. Before connecting the valves to existing shower riser outlet and hot and cold water inlet, a crimp ring should be used for each connection. Insert a coupling before adding a connecting tube. Tighten the connection by using a crimping tool.

6. Remove the cartridge from the shower valve by taking out the plaster ground, pull out the retainer clip and then remove the cartridge using pliers. You can then solder the tub drop outlet connection.

7. Turn on your home’s water supply and let the water run for about 15 seconds. Doing so will flush the system, and will tell you if there are leaks with any of the connections.

8. Turn off the water supply, and then reinsert the cartridge, with the notched side up, and then reattach the retainer clip.

9. Attach the shower flange into the wall. Make sure to wrap both ends with a thread seal tape and apply plumber’s putty on the back of the flange. Thread the shower arm into its designated area and then push the flange into the wall.

10. Screw on the shower head and tighten using the wrench. Then, install the tub spout.

11. To install the shower valve, slide the top tube onto the valve and then screw the escutcheon in place. Make sure the hot and cold are in the right position.

12. Afterwards, test the water temperature. Make sure it is 120 degrees and below.

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