A pressure reducing valve is usually located right where the water comes into the house. Most of the common PRV setups will have an adjustment to set the pressure for your home. Typically you should set your water pressure anywhere from 50-80 psi. Some people don’t like the idea of reducing their water pressure. However you should keep in mind that your fixtures also have restrictors that are going to be more restrictive than a water pressure set to 50 psi.
You can easily test the water pressure in your home by hooking up a water pressure gauge to on of your exterior hose bibs. We can come out to check your water pressure and verify that your prv valve is working. It is very common for these to go bad and need to be replaced.