What Causes Low Water Pressure in Kitchen Sinks?

It can be quite frustrating to have your kitchen sink loose water pressure. So, I did some research and wrote this article on common causes for low water pressure in your kitchen sink.

So what causes low water pressure in kitchen sinks? Low water pressure in kitchen sinks is generally caused by a clogged aerator or a cartridge. Water line breaks, routine repairs and leaking toilets are contributing factors too. Sometimes, a closed shut-off valve or Pressure Reducing Valve (PRV) could also be the cause.

The kitchen sink is one of the most used areas in the home. And, a loss in water pressure can slow you down. In this article, I have listed out the most common causes and their fixes. So, I hope you find the information presented in this article useful.

What Causes Low Water Pressure in Kitchen Sinks?

There can be many causes of low water pressure in your kitchen. First, check to see if the water pressure is low only in your kitchen or other areas as well. If it is only the kitchen sink, the most likely causes could be:

  • Clogged faucet aerator
  • Blocked faucet cartridge

If the water pressure is low in all other areas too, it is most likely caused by one or more of the following:

  • Water line breaks
  • Leaking toilets
  • Shut-off valves
  • Pressure Reducing Valve (PRV)

In some cases, you can fix the issues with the right tools. For some others, it may be best to leave the fixing to a certified plumber. Let’s look at all the possible causes below.

Faucet Aerator

An aerator is a device that controls the flow rate and is usually found near the tip of the faucet. Often, minerals, particles or debris may clog up the aerator. As a result, your kitchen sink may end up losing water pressure. In most cases, cleaning the aerator should restore the water pressure.

You can remove the aerator by twisting it counterclockwise with your hand. If it seems hard to open by hand, you can use a pair of slip-joint pliers with tape around its teeth to get a better grip. Once removed, you can soak the aerator in vinegar and brush off the sediments. Generally, soaking the aerator overnight should be enough. In conclusion, if the particles are too stubborn to come off, you can always get a replacement.

Faucet Cartridge

A clogged faucet cartridge could also cause low water pressure in your sink. The cartridge controls the water flow in your faucet. In other words, when you twist the handle open, the cartridge opens the valves allowing the water to flow. As you will see, cleaning out the cartridge is a little more involved than cleaning the aerator.

Before starting to dismantle the faucet, close the shut-off valve and let all the water run out. This is to ensure no residual water remains in the line. Afterward, close the sink’s stopper so that no debris escapes into the drainage. Now pry off the handle cap using a flat screwdriver. After removing the handle, you can use a pair of slip-joint pliers to remove the retaining nut. It would help to stick tape around the teeth of the pliers to added grip. Furthermore, it would prevent the faucet from getting scratched. Then, pull off the retaining clip using a pair of regular pliers. Finally, you will be able to pull out the cartridge from the opening.

You can clean the cartridge by soaking it in vinegar overnight. Scrape off the sediments with a hard bristled brush. Yet, if you feel the sediments are too stubborn to come off, you should consider replacing it.

Water Line Breaks

A break in your water lines can occur from time to time. Yet, detecting them may not be so easy. If not only your kitchen sink has lost water pressure, a break in your water line is very possible.

You can confirm if there is a break somewhere in your water lines by taking the meter reading. That is, close all faucets and water outlets, and take the meter reading. After about four hours, take another reading of the meter. A change in the readings would be an indicator of a leak caused by a break in the water lines somewhere.

In the event of a potential break in the water lines, you should call a professional plumber to have look.

Leaking Toilet

Leaking toilets can cause low water pressure in the kitchen sink and other areas as well. Some of the causes of leaks are a break in the supply lines or toilet tank. Further, there could be a stuck flapper, fill valve or float that is causing the leak. Furthermore, it could even be faulty connections or a warped flapper.

Although you can attempt to fix it yourself, I recommend calling a certified plumber. They have plenty of experience dealing with these kinds of issues.

Shut-off Valve

The shut-off valve shuts the water off to the kitchen sink and is usually located under it. Since this valve is not always operated, mineral deposits tend to build up over the years. Thus, weakening the washers. Sometimes, there is a tendency for leaks to develop near the stem of the shut-off valve too. Anyhow, it is always a good idea to first see if the valve is completely open. Above all, a closed shut-off valve could have been the only cause of the low water pressure to the kitchen sink. If your kitchen sink has two shut-off valves (hot and cold water), inspect if both or only one needs to a replacement. Most of the time, it is easier to replace than to try and get a faulty shut-off valve to work.

Before attempting to replace, close the main water line so that the water will not disrupt your work. First, remove the water line connecting to the shut-off valve, use a wrench to loosen the nut. You can remove it by turning it counterclockwise. Next, remove the compression nut that secures the shut-off valve in place. Removing the compression nut will make a shut-off valve come off.

Make sure you get the identical shut-off valve to replace. Tighten the compression nut to secure the new valve in place. But, don’t tighten too much or you damage the nut or the pipe. Finally, reconnect the water supply line and tighten its nut.

Pressure Reducing Valve (PRV)

The PRV (also known as Pressure Regulator) is usually located on the line where it enters the home or office. It’s shaped like a bell and pre-set by the manufacturer. Adjust and see if it affects the water pressure or for any signs of damage.

If you feel the problem is with the PRV, You can replace it yourself or call a certified plumber to fix it. In case you decide to do it yourself, make sure you close the master shut-off valve first.

Related Questions

What causes low hot water pressure in the kitchen sink? The most likely cause is sediment built up in your water heater.  But, if the problem seems to be only in your kitchen sink, it is most likely caused by blocked valves. First, check to see if the valves are completely open. Then, if your faucet has two handles, check the hot water handle’s cartridge for any blocks.

Why does my sink sprayer have no pressure? Your sink sprayer could have lost pressure due to a blocked, damaged or worn-out hose. A faulty diverter could be the cause too. The diverter distributes water from the faucet to the sprayer. Besides, check the aerator in the sprayer for any blocks.

How do you fix a stuck kitchen sink sprayer? First, look for any leaks in the hose, the diverter and the connecting nut under the sprayer head. If you don’t find any leaks, check to see if the pressure in the faucet is normal. If so, the problem could be the aerator in the sprayer. In that case, remove the aerator and soak it in vinegar overnight. Then, take a hard brush and brush off the built-up sediments. If the sediments seem to stubborn to come off, replace the aerator with a new one.

Why is the hot water pressure low in the whole house? The most likely cause for this is sediment build up in the hot water tank. Also, hard-water build up in the lines can block the water flow in and out of the heater.

2 Comments

  1. it is very helpful to guide to remodel my bathroom. I appreciate your hard work. Wonderful article for kitchen sink. Why My bathroom shower valve can not flow water perfectly?

    • Hi Lawrence. I’m glad you found this article useful. The most probable cause for your faulty shower is a damaged valve cartridge. Or, it could be because of a worn-out rubber ring in the valve. In most cases, replacing the cartridge would solve the problem.

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