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. Only go one full revolution at a time and get a new pounds per square inch (PSI) reading with your pressure gauge.
Adjust the Pressure
The regulator will have a screw or bolt and a locking nut system. Loosen the locking nut with a wrench and using quarter-turn increments, use a screwdriver to turn the screw counter-clockwise (to the left) to decrease water pressure, and clockwise (to the right) to increase water pressure.
If you tighten the screw the water pressure will be more and if you loosen the screw the water pressure will be less. Turn the screw clockwise to tighten it and increase the pressure, or turn it counterclockwise to decrease the pressure.
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.
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.
After installation, test the water pressure, and adjust the regulator, if necessary. To adjust, loosen the locknut on the adjustment screw, then turn the screw up or down until the water pressure is at the desired level, as measured by a pressure gauge attached to a threaded hose bib somewhere in the home.
This is a serious concern—water pressure that's too high is difficult to contain, and could leak to plumbing leaks, worn seals, and damaged fixtures. It could even shorten the lifespan of your appliances that depend on a water connection like your washing machine, ice maker, dishwasher, and more.
If you wish to reduce the water pressure to a particular faucet, turn the valves clockwise by a quarter rotation. Make sure to turn the cold and hot water valves equally to create more consistent water pressure.
The AWWA operating formula for opening/closing a gate valve is 3 times the nominal valve size plus 2 or 3 turns of the operating nut. For example, a 6-inch gate valve would require 6 x 3 = 18 turns plus 2 or 3 turns, for a total of 20 to 21 turns.
Having worked in the specialty chemical field and pharmaceutical manufacturing I can say that using 90-degree elbows affect flow. Those who have studied and used engineering principles in constructing piping systems will always use two 45-degree elbows rather than one 90-degree elbow.
In a water flowing pipeline, water pressure and pipe size are dependent on each other. If the diameter of a pipe decreases, the pressure in the pipe will automatically rise. As per the scientific approach, pressure can be reduced by reducing the area of conveyance.
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 most accurate method is to buy a pressure gauge from your local hardware store and hook it up to a hose faucet/bib. Check the pressure when all other faucets and water-using appliances are turned off to get a baseline reading. In general, you want the household plumbing to provide between 30 and 80 psi.
Building code requires that homes that receive water with pressure greater than 80 PSI have a water pressure regulator. A home's water pressure should stay in the range of 40 to 60 PSI.
Normal water pressure range
In general, residential water pressure ranges between 45-80 psi (pounds per square inch). If your water pressure is under 40 psi, it's considered low. A psi between 20-30 is considered very low, and under the minimum water pressure required by most building codes.
(Normal is 60 psi and very few areas are below 40 psi) The pressure of the streams will drop under these extreme conditions, of course, but the stream integrity is preserved. This photo shows the stream integrity of our Perfect shower head (old style).
One of the main giveaways of high house water pressure is noise. Banging sounds coming from the pipes usually indicate a problem with pressure, and these noises tend to be very noticeable when the water pressure is too high.
The water shutoff valve is what controls the flow of water into your home. Only if it is fully open will you have full water pressure. Low water pressure could result if it is only partially open.