The pressure regulator is designed to maintain a constant water pressure in plumbing systems that have one installed. It is usually set by the manufacturer to around 45-60 psi, so adjustments aren't usually necessary. If you have low water pressure, try adjusting the regulator.
One of the most common causes of low pressure to a kitchen or bathroom sink faucet is debris or mineral buildup in the aerator. The aerator is the tiny screen that you see at the end of your faucet.
Since the EPA limits water flow at 2.2 gpm, most modern faucets now come with a pre-installed aerator that limits the flow to 2.2 gpm while also infusing the water stream with air to reduce splashing.
Partially Closed Valve
One of the most common issues that can lead to low water pressure problems is that the water is being obstructed by one or more partially closed shutoff valves. Typically, a home will have one main shutoff valve located inside the house.
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.
Check Your Faucet Cartridge
Your faucet cartridge sits deeper in your faucet than your aerator and has a hole through which water passes. These cartridges become clogged or blocked by hard water build up which produces low water pressure in kitchen faucets. Often, they just need to be cleaned.
Some of the first signs of a failing pressure regulator are a leaking water heater or commode. The water coming from a faucet may also exit with such force that splashing or water “hammering” may occur.
If your valves are open all the way and you're still experiencing slow water flow, then the cause might be a clog. The first place to check is the aerator. The aerator is the cap on your faucet where the water comes out of. It has a screen and, over time, sediment gets caught in it, which impedes water flow.
If the kitchen is the only tap with low pressure, it's time to consider the potential causes of low water pressure in a kitchen sink so you can determine what might be causing it, and fix it. The most common causes of low water pressure in a kitchen sink are a clogged aerator or a clogged cartridge.
Please keep in mind that all new faucets since 1994 are restricted to conserve water per EPA code mandates. Older faucets had no restrictions. Beyond intentional flow restriction, new installations can sometimes have reduced flow if the lines are not flushed prior to installation of aerators or shower heads.
Water pressure regulator replacement: $250 to $1,000. Pipe section replacement: $500 to $4,000.
PRV Age. The spring in the diaphragm can lose tension over time. Make sure you replace your PRV every 4-5 years to avoid problems due to age.
The good news is that you can easily replace faucet aerators, clean showerheads to remove limescale, or simply buy new fixtures to replace the defective ones, which can improve your water pressure. However, it is important to know that repairing or replacing faucets and fixtures is only a temporary solution.
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.
The screw acts as a water pressure regulator. 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.
Flow restrictors are usually found in the neck or threaded end of the shower head exposed when the shower head is removed from the shower arm as shown in the image below. They would appear in the opening of the aerator when it is removed from a lavatory or kitchen faucet.
A water flow restrictor is usually a flat, circular, plastic piece. The center of the restrictor is shaped like a star, or similarly shaped, and comes in a variety of colors.
Faulty Faucet
Over time, wear and tear can cause the seals in the faucet to break down, which can lead to leaks. These leaks can then reduce the overall water pressure. If you think that your faucet is the cause of your reduced water pressure, you might have to get the faucet repaired or change it altogether.