The adjustment screw raises and lowers the water pressure, but before it can be adjusted, you need to loosen the lock nut below it. Loosen the lock nut by half a turn with the crescent wrench. Turn the adjustment screw counterclockwise to lower the pressure or clockwise to raise the pressure.
Loosen the lock nut on the pressure reducing valve with a wrench and back it off by unscrewing it. Fit a socket wrench over the adjustment nut on the top of the valve. Turn the nut counterclockwise to reduce the pressure downstream from the valve and clockwise to increase it.
A PRV will sit in-line on a mains inlet pipe. It allows the user to adjust the desired outlet/downstream pressure, usually via a dial or wheel on top of the valve.
Normal psi for a home pipe system is between 30 and 80 psi. While you don't want the psi to be too low, it violates code to be above 80. Instead, you should aim for a psi that's between 60 and 70.
A water pressure regulator is a dome-shaped brass fitting that is generally found just past the main shutoff valve, where the main water line enters the house. It usually has an adjustment screw on top.
A water pressure regulator, if you have one, is usually located where the main water line comes into the house and after the main shut off valve. This way if you need to work on or change the water pressure regulator you can simply shut off the water main to do so.
On top of the regulator should be an adjustment screw and a lock nut. The adjustment screw raises and lowers the water pressure, but before it can be adjusted, you need to loosen the lock nut below it. Loosen the lock nut by half a turn with the crescent wrench.
Water Pressure Readings
Normal water pressure is generally between 40 and 60 PSI. Most homeowners prefer something right in the middle around 50 PSI. Once you measure the water pressure in your house, you can adjust it to a setting that is ideal for all family members and household uses.
While it is possible to remove flow restrictors from shower heads, we strongly advise against it for several reasons. Flow restrictors for faucets are an integral part of most aerators and it is generally not possible or desirable to remove them.
Open your main water valve.
Find the valve and check to see if it's completely open. Opening a half-shut valve is one of the quickest ways for increasing home water pressure. Sometimes the main valve is turned off accidentally during routine repairs and maintenance without the homeowner's knowledge.
Do All Homes Have a Water Pressure Regulator? No, and in some cases, you may not need one. Certain municipal supplies regulate their water pressure safely, but if that pressure runs above 80 psi, you'll want to protect your plumbing system by installing one.
While pressure-reducing valves reduce or limit incoming pressures, pressure regulators maintain constant outlet pressures regardless of upstream or downstream fluctuations.
The relief valve setting(s) should be at least 10% or 15-psig, whichever is greater, above the maximum operating pressure. Where unstable process conditions exist, this differential should be at least 10% above the maximum operating pressure or 25-psig, whichever is greater.
Pressure-reducing valves are used when maintaining consistent levels of pressure throughout an entire system is necessary, while pressure-relief valves are used when it's essential that extreme overpressure conditions be prevented from occurring within the system.
Most residential plumbing systems are designed to handle 40 to 60 PSI of pressure, with 80 PSI being the typical maximum and anything over 100 PSI being possibly detrimental to plumbing components.
The typical inlet water pressure to a standard size home is usually between 40 to 45 pressure-per-square-inch (psi). For a standard household, it should never exceed 60 psi— that's why many plumbers automatically set your pressure regulator to 50 psi.
Find the spigot closest to your source of water. Make sure all the taps and other water uses are turned off in your house. Now turn on the spigot and see how long it takes to fill the bucket. Dividing the number 60 by the time to fill the bucket will give you the gallons per minute number.