If your sink makes a whistling, squealing, or high-pitched noise when you turn the water on or off, it’s usually caused by water being forced through a restricted opening. While the sound can be alarming, it’s typically a mechanical issue rather than a serious plumbing failure.
In most cases, the noise is coming from a small component under pressure.
Quick Answer:
A sink makes a whistling noise when water flows through a restricted or worn component, such as a partially closed shutoff valve, clogged aerator, damaged washer, or failing cartridge. The restriction causes water to vibrate, producing a high-pitched sound.
Why This Happens
When water moves through narrow or damaged openings, it can create vibration. That vibration travels through pipes and fixtures as a whistle or squeal.
Common causes include:
- A partially closed shutoff valve under the sink
- A clogged or damaged aerator
- Worn washers inside the faucet
- A failing faucet cartridge
- High water pressure amplifying vibration
Whistling noises are different from sink gurgling, which is caused by airflow issues in the drain system.
Step-by-Step: How to Stop a Sink Whistling Noise
Step 1: Check the Shutoff Valves
Look under the sink for the hot and cold shutoff valves.
- Make sure both valves are fully open
- Turn counterclockwise until they stop
Partially closed valves are a very common cause of whistling sounds.
Step 2: Remove and Inspect the Aerator
Unscrew the aerator from the faucet tip.
- Check for debris or mineral buildup
- Rinse thoroughly
- Reinstall or replace if damaged
Aerator restrictions often create high-pitched noises.
Step 3: Test Hot and Cold Water Separately
Turn on hot and cold water individually.
If:
- Only one side whistles
…the issue is likely isolated to that supply line or internal faucet component.
Step 4: Observe When the Noise Occurs
Pay attention to timing.
Whistling may occur:
- Only when the faucet is partially open
- When water is turned on quickly
- When the faucet is turned off
These patterns help identify which part is vibrating.
Step 5: Consider Internal Faucet Wear
If basic checks don’t resolve the noise, worn internal parts may be vibrating under pressure.
This often overlaps with issues that cause faucet dripping or low water pressure.
What Not to Do
- Don’t ignore persistent whistling
- Don’t overtighten shutoff valves
- Don’t assume the noise will fix itself
- Don’t disassemble the faucet without shutting off water
Noises usually worsen as components continue to wear.
When to Call a Professional
Call a plumber if:
- Whistling continues after basic checks
- The noise is very loud or constant
- Multiple fixtures make similar sounds
- You suspect high water pressure
Some noise issues require pressure regulation or internal repairs.
Safety Notes
- Shut off water before disassembling faucet parts
- Avoid forcing stuck components
- Check for leaks after adjustments
- Monitor the sink after repairs
Common Homeowner Questions
Is a whistling sink dangerous?
Usually not, but it indicates wear or restriction that should be addressed.
Can high water pressure cause whistling?
Yes. High pressure can amplify vibrations inside valves and faucets.
Will replacing the faucet stop the noise?
Often, yes — especially if internal parts are worn and unavailable separately.