A noisy kitchen faucet may start as a mild irritation, but it won't go away on its own. When you find yourself avoiding turning on the water because your kitchen faucet is so noisy, you know it's time to roll up your sleeves and investigate the source of the problem. The noise typically emanates from either the pipes or the faucet, so you'll need to do a little detective work to narrow your focus and correct the issue.
Pipes or Faucet?
What kind of noise is it, and when does it occur? If your kitchen faucet makes a squeaking noise whenever the handle is turned, then you know it's likely an issue with the washers or threads in the faucet. High-pitched whistling sounds also indicate that you should investigate the faucet.
On the other hand, if you hear a banging sound a few seconds after the water is turned on, then the problem is in the pipes.
Finding the Source in Faucet
If you believe the problem originates in the faucet, you'll need to disassemble the faucet and look for any sediment blockages or worn-out parts. Water that passes by a loose washer, for example, will cause it to vibrate and produce a sound.
Start by turning off the hot and cold water valves under the sink. Then twist off the end of the spout to remove the aerator (or use the aerator key that came with your faucet if it has a "hidden" aerator). Inspect the aerator and/or the check valve for signs of sediment buildup caused by hard water. If you're able to remove visible buildup, turn the water valves back on and let water run out of the spout without the aerator on to see if the sound continues.
If removing the aerator solved the problem, clean it thoroughly or replace it altogether. If the sound continues, turn the valves off again and remove the faucet handle to reveal the cartridge. Look for mineral deposits and any worn-out parts. Scrub every surface within the faucet handle to remove any sediment or debris, reassemble the handle and see if the sound continues.
Finding the Source in Pipes
If you believe the sound is coming from the pipes under the sink, the first step is to pinpoint whether it's the hot water supply or the cold water supply. Turn on just the hot water tap and listen for the noise. Then repeat with the cold water tap.
When only one water source seems to be the culprit, check to make sure the corresponding valve is open all the way. When the valve is only partially open, the water pressure will build at the valve as a large quantity of water struggles to fit through a small opening. These water valves aren't designed to regulate water this way, but your faucet is. Control excess water volume and pressure at the faucet rather than at the water supply valve.
If both taps produce the sound or the sound occurs right after you close the taps, then the issue could be "water hammer," which Plumbing Mart explains is caused by the pressure of the water slamming into the closed water taps. Possible solutions include reducing your home's overall water pressure at the main water line or water meter or installing an air chamber to "catch" the water when it suddenly has nowhere else to go. In turn, this prevents the pipes from banging into the walls and causing a racket.