From water savings to kinder flow, faucet aerators are small but necessary parts of any faucet set up. Today's market has a host of different faucet aerators, including low-flow, aerator adaptors for water filtration systems, laminar aerators for healthcare facilities, etc. Ultimately, though, all aerators have the same basic function: mixing air into the water flow.
By definition, an aerator adds air. Put one on the end of your faucet and it will add air to your water flow. If you have ever run a faucet without an aerator, you realized the purpose of an aerator. Without one, water sprays out with unpleasant force and causes splashing. Mixing air into the flow of water produces a steadier, more stable stream. An aerator is usually a simple, mesh screen made of metal or plastic that is attached to the end of a faucet with some sort of housing. As water flows through this screen it is divided into many small streams with air in between. This allows for the feeling of high pressure with less actual water consumption.
Faucet aerators are actually a great way to cut down on water usage, lower utility bills, and preserve the environment with very little investment. Most faucet aerators are marked with the amount of water they allow to pass through. This is measured in gallons per minute, and there are four general categories. If an aerator says it is "full flow" it doesn't restrict water usage aside from the small amount that is naturally conserved by using an aerator, meaning that whatever the flow rate of your faucet the aerator will be about the same. "Standard" water flow for aerators is 2.2 gpm, while "water saving" flow is considered 0.5 gpm - saving up to 75% more water in comparison to a standard flow. The beauty of an aerator is that you probably won't even notice the difference.
How To Figure Out Which Aerator You Need
The most basic thing you need to know about your faucet in order to replace or add an aerator is the threading - either male or female. If your kitchen faucet has threads on the outside, it is male threaded - which means you need to buy a FEMALE threaded aerator to fit over it. Conversely, if your faucet has threads on the inside, it is female threaded and you'll need a MALE threaded aerator.
Once you've determined whether you need a male or female aerator, you'll need to determine the size. Typical "Regular" size for a faucet aerator is 15/16" male threaded or 55/64" female threaded, while "Junior" size is 13/16" male threaded or 3/4" female threaded. Some faucets use a smaller "Tom Thumb®" metric-size aerator, which is M18x1 male threaded or M16x1 female threaded. But wait! Before you get out your tape measure, there's a very easy way to tell what size replacement aerator you'll need.
First, take the existing aerator off your faucet - usually this just unscrews, although you may need a wrench if it's on there tight. Then grab some spare change from the couch or your rainy day jar, specifically a quarter, a nickel, and a dime. Place the coins over the aerator. If your current aerator is about the size of a quarter, you'll need a "Regular" sized replacement. If it's about the size of a nickel, you have a "Junior" size aerator. If your aerator is approximately the size of a dime, you'll need a "Tom Thumb®" size aerator.
Remember that some faucets are oddly sized and you may need an adapter - either to change the threading of your faucet or to ensure a proper fit. After you've figured out what size aerator you'll need and whether or not you'll need an adapter, it's time to decide what kind you need. Not all aerators produce the same type of stream, and some have special features for a variety of applications.
Stationary vs. Swivel - The basic aerator screws onto the end of a faucet and is not intended to move. However, more elaborate aerators are designed in a swivel style and allow the water to be directed in several directions. Sometimes these models have a dual stream function that allows you to change the type of stream by pulling on or retracting the aerator.
Diverter-Style - Special aerators are equipped with a small outlet on the side to have a hose attached to them. This allows you to divert water to a water filter without sacrificing the convenience of an aerator.
Aerated vs. Spray vs. Laminar - There are three main ways faucet flow devices affect the stream of water coming from the tap. The typical aerator is what's most often used in homes and apartments and the only one that truly mixes air into the water. It produces a larger, whiter aerated stream that is soft to the touch and non-splashing. Spray aerators offer a miniature shower pattern to provide full, non-splashing coverage during hand washing and are typically used in public restrooms. Laminar flow devices give you a crystal clear, non-splashing, 100% water stream that is most useful for high flow applications or healthcare facilities.
If the water pressure has decreased in your faucet, the aerator may be the culprit. The tiny mesh of the aerator can get clogged with silt and debris, or with the buildup of minerals from the water. However, this is usually a quick and easy fix. To clean the aerator, simply unscrew and remove the mesh. It may simply need rinsing and scrubbing off with a small brush, like an old toothbrush. Mineral buildup can be removed by soaking the aerator in a 50/50 solution of water and vinegar for several hours, or using a mild descaler, such as Lime-Away. Flush the faucet before replacing the aerator to get rid of any unwanted sediment. If the buildup will not come off, replacing the aerator is an inexpensive and easy solution to getting your water running smoothly again.