What to Check First If Only One Faucet Has Low Water Pressure

Noticing low water pressure in just one faucet can be frustrating, especially when everything else in your home seems to be working fine. If you’ve ever turned on your sink and wondered what’s causing such low water pressure – you’re not alone.

Before you panic or call a plumber, there are a few quick things you can check. At Covenant Plumbing, we help homeowners every day with problems like this, and in many cases, the fix is easier than you’d expect.

1. Check the Faucet Aerator for Build-Up

The most common cause of low water pressure in a faucet is a clogged aerator, the small screen at the tip of your faucet where the water comes out. Over time, sediment and minerals from your water (especially if you have hard water) can clog the holes and block the flow.

Twist off the aerator at the tip of the faucet. If it’s hard to turn, you may need pliers. Rinse it off or soak it in vinegar to break up any buildup. After cleaning, screw it back on and see if the water pressure improves.

2. Make Sure the Water Valves Are Fully Open

Look under your sink. You should see two shutoff valves – one for hot water and one for cold. If one of these valves isn’t fully open, it could be restricting the water flow to that faucet.

Turn each valve counterclockwise until it stops, which means that it’s fully open. Then turn your faucet on again to check the pressure. This is an easy thing to overlook, especially if you’ve recently had work done in the area.

3. Test Both Hot and Cold Water Pressure

This is a quick way to narrow down the problem. Try turning on just the cold water, then just the hot.

If both hot and cold are weak, the problem is likely in the faucet itself or the supply line underneath. If only one side is weak, it could be a separate issue, like a problem with your water heater or a blocked hot or cold line.

4. Check the Faucet’s Cartridge or Internal Parts

Inside your faucet is a small part called a cartridge or valve. Over time, these parts can get clogged with debris or wear out, especially in areas with mineral-heavy water.

If you’ve already cleaned the aerator and checked the valves, and your faucet still has low pressure, this could be the issue.

Turn off the water under the sink, then remove the faucet handle and cartridge. You may be able to clean it and reinstall it, or you might need a replacement. If you’re not sure what to look for, it’s a good time to call a plumber.

5. Look at the Supply Hose Under the Sink

Sometimes the issue isn’t inside the faucet, but in the flexible hose or pipe bringing water to it. A bent, kinked, or damaged supply line can reduce flow to just one faucet while the rest of your plumbing works fine.

Inspect the line beneath the sink. If it looks pinched or bent sharply, that could be your culprit. Replacing the line is usually inexpensive and can restore pressure quickly.

Still Have Low Water Pressure in Just One Faucet?

If you’ve tried these steps and your faucet still has low pressure – or you’re just not comfortable disassembling parts of your plumbing – don’t worry. A professional plumber can quickly figure out what’s going on and make sure everything is working like it should.

Whether you’re dealing with a low water pressure tap in your bathroom or a kitchen sink that suddenly has weak flow, these issues are more common than you might think, and most have simple solutions.

Covenant Plumbing: Serving Bloomington, IL Since 2006

At Covenant, we’ve helped countless Bloomington homeowners get their water pressure back to normal. As your trusted local plumbing team, we’re always here to offer honest answers and reliable service when you need it most.

Call (309) 340-1403 for help today!