“An aerator contains a screen and a water reducer/aerator washer,” says to Bob Beall, a plumber in the Northeast Ohio and Southwest Pennsylvania region. “These little items have a habit of collecting bits of naturally occurring mineral sediment in the water.” “What becomes noticeable when the aerator becomes clogged is a reduced water flow at the spout (on both hot and cold) and/or a non-symmetrical spray coming from the spout,” according to Beall.
Below are Beall’s tips for cleaning your aerator.
No. 1. To remove the aerator from the faucet simply turn it counterclockwise. Drop it straight down so you don’t lose any internal parts, especially the thread-sealing gasket. The threads can be either inside or outside the cap. If the cap is stuck, you will need pliers to turn it.
BONUS TIP: Tape the jaws with electrical tape to minimize scratching.
No. 2 Look inside the center area for sand, silt, and other waterborne debris.
No. 3 Take the center section out to check for further debris, noting the order in which things come apart.
No. 4 Check for anything stuck in the screen.
No. 5 In the flow reducer, look in the tiny side holes and the center hole of the white button for debris.
Note that if do not put all the pieces back together properly, there will be a leak or the water flow will not be a smooth aerated flow.
Despite even the most experienced plumber’s intentions, it’s easy to let the parts of an aerator fall out when removing it. To prevent permanent loss of any parts, put the stopper in the sink drain before removing the aerator. If it is necessary to take the aerator away from the sink, to keep from losing parts, disassemble it over a bowl.
Source: Mr. Rooter Plumbing