Noisy Faucet (Whistling / Hammering)
Updated February 20, 2026
Whistling, screaming, chattering, or banging -- each sound has a specific cause. Whistling means restriction. Chattering means worn washer or cartridge. Banging when it shuts off is water hammer. Match the sound to the fix.
Overview
Each noise has a different cause. High-pitched whistle while running: water forced through a restriction (clogged aerator, worn cartridge, partially closed valve). Chattering or vibrating: loose washer or seat in a compression faucet. Loud bang when shutting off: water hammer from sudden flow stoppage. Match the sound to the cause -- wrong fix for the wrong noise solves nothing.
Symptoms
- High-pitched whistle while running -- worst at partial open, may stop when fully open
- Chattering or vibrating at a certain handle position -- stops when you move the handle slightly
- Loud bang when turned off quickly -- water hammer, may shake visible pipes
- Humming or droning while running -- turbulence or resonance in the supply line
- Noise on hot or cold side only -- problem in that specific supply line or valve
- Started suddenly after plumbing work, new faucet, or pressure change -- something in the system changed
Common Causes
- Clogged aerator -- minerals, sediment, or debris narrow the openings. Water forces through and whistles. Most common cause, easiest fix.
- Worn cartridge or washer -- internal wear creates uneven passages that vibrate or whistle. In compression faucets, the rubber washer gets loose, cracked, or hardened and chatters against the seat.
- Water hammer -- fast-moving water stopped suddenly. Single-lever ceramic disc cartridges close almost instantly, making them prone to hammer. Pressure wave reverberates through the pipes.
- High water pressure -- above 80 PSI increases velocity through every fitting, making existing noise louder and hammer more severe.
- Worn valve seat -- pits, grooves, or rough spots from corrosion. Washer cannot seal cleanly, water forces through the gap and vibrates. Noise at specific handle positions where the gap resonates.
What You'll Need
How to Fix It
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Identify the Noise Type and Timing
When does it happen? While running (whistle, hum, chatter) or when shutting off (bang)? All flow rates or specific handle position? Hot only, cold only, or both? This faucet only or multiple fixtures? Whistle at partial flow: restriction. Chatter at specific positions: worn washer. Bang when shutting off: water hammer. Multiple fixtures: systemic (high pressure or missing arrestors).
Tip: Only at a very specific handle position, stops when you move slightly? Almost certainly a worn washer or cartridge vibrating at that flow rate. -
Clean or Replace the Aerator
Simplest fix first. Unscrew the aerator (counterclockwise, pliers with cloth to protect finish). Disassemble: mesh screen, restrictor disc, gaskets. Rinse, scrub with a toothbrush. Heavily clogged or damaged? Replace ($3-8). Reinstall, test. Fixes the majority of whistling problems.
Tip: Aerator off? Run the faucet briefly to flush sediment from the supply line. Upstream debris is often what clogged it. -
Replace the Faucet Cartridge or Washer
Aerator clean, noise persists? Internal valve component. Single-handle: water off, handle and trim off, extract cartridge, replace with brand/model match. Compression (two-handle): handle and bonnet nut off, pull the stem, replace the rubber washer and O-ring. Valve seat pitted or grooved? Resurface with a seat grinder or replace if removable.
Tip: Plumber's grease on the O-rings before inserting the new cartridge. Smooth operation and proper seal reduces noise from improper seating. -
Install Water Hammer Arrestors
Bang when shutting off? Hammer arrestors on the hot and cold supply lines. Small sealed cylinders with a piston and air chamber that absorb the pressure wave. Install between shutoff valve and supply line, standard threads. Mini-arrestors for under-sink spaces. Banging stops immediately.
Tip: Hammer at multiple fixtures? Whole-house arrestor on the main line, or recharge the system's air chambers by draining and refilling. -
Check and Reduce Water Pressure
Aggressive flow, splashing, or noise at multiple fixtures? Test pressure (gauge on a hose bib, $10-15). Above 80 PSI? Contributing to the noise. Adjust the PRV on the main line to 50-60 PSI. Lower velocity reduces whistling and lessens hammer.
Tip: Even at normal pressure (50-60), dropping 5-10 PSI can eliminate marginal noise. Sometimes right at the threshold. -
Check Supply Line Valves and Connections
Shutoff valves fully open? Partial open creates a restriction that whistles or hums. Check supply lines -- braided stainless can develop internal restrictions if the rubber liner deteriorates. Noise started after new lines? Try a different set. Loose pipes amplify vibration -- secure with straps or clips.
Tip: Flexible lines can resonate at specific flow rates. Replacing the line stops the noise? Old line had an internal issue. Noise moves to the new line? Problem is upstream.
When to Call a Pro
Call a plumber if the noise persists after aerator, cartridge, and pressure checks, if hammer is severe and system-wide, if the noise is inside the wall and you cannot find it, if the PRV needs replacing, or if it started after recent plumbing work. A plumber can also resurface valve seats with specialty tools.
Prevention Tips
- Clean aerators every 3-6 months. Prevents mineral buildup that causes whistling.
- Replace cartridges every 8-12 years. Internal wear creates noise before it causes leaks.
- Maintain pressure at 50-60 PSI. High pressure amplifies every noise condition.
- Hammer arrestors near quick-closing valves: single-lever faucets, washing machines, dishwashers.
- New faucet? Flush the supply lines before connecting. Removes debris that would immediately clog the aerator or cartridge.
- Secure loose pipes with straps or cushioned clips. Loose pipes amplify vibration and turn a quiet faucet issue into a loud wall noise.