Written by: Alexandra Uta // Last Updated: Sep 20, 2022
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Under sink water filters are one of the most popular water filtration options among domestic users.
Many households have one nowadays, and purchasing a system for your home can be a great investment if you’re concerned about the quality of your drinking water.
If you’re curious about how exactly under sink water filters work, this article is for you.
Key Takeaways
An under sink water filter gets installed under a kitchen or bathroom sink. It filters the water before it comes out of the faucet above.
These are the different types of under sink water filters:
Also, some under sink water filters feature an inline design. They attach to the existing faucet. Others require a separate dispenser.
Under sink water filters are water filtration systems designed to seamlessly attach to your main plumbing and provide you with a constant supply of purified water.
Installed under the sink, they don’t take up any countertop space like filter pitchers do, and they provide you with clean water on demand, instead of having you wait until a certain amount has been purified.
The main idea behind an under sink water filter is that you hook it up to your plumbing and dispense water through your faucet as you normally would. Some under sink water filters also come with their own faucet, making it easier to install them in difficult spots.
Under sink water filters are mainly categorized based on their filtration process.
Single-stage under sink water filters only run your water through one filter element, such as a carbon block. This usually results in less thorough filtration, but also comes with some benefits like taking up less space, working faster, and costing less.
Depending on the contamination levels you’re dealing with in your home, a single-stage under sink water filter could be perfectly sufficient for your situation.
On the contrary, multi-stage systems run the water through several filtration steps, removing more and different types of contaminants and often also improving its quality in other regards.
For example, a multi-stage under sink system may incorporate a sediment filter in its first stage removing floating particles. This could be followed by a granular activated carbon filter ideal for removing chemicals and chlorine taste and odor. A carbon block filter in stage 3 could be used to get rid of even more chemicals and heavy metals.
Reverse osmosis is a special type of water purification which uses a combination of high pressure and a membrane with tiny pores to remove contaminants. Water is forced through the membrane, which is designed to only let water molecules and other small elements through, leaving almost all contaminants behind.
An inline under sink water filter attaches directly to your plumbing and filters water before it reaches your existing sink faucet. This allows you to have your water filtered in an unobtrusive manner that doesn’t require you to use a separate dispenser or make any special changes to your kitchen’s layout.
On the other hand, some models have their own dedicated faucet for dispensing water. This means that you need to make room on your countertop for it, and you may also have to deal with a more complicated installation process that requires you to drill a hole in your countertop or sink.
Under sink water filters are designed to be as unobtrusive as possible, operating in a spot where you can’t even see them most of the time. This makes them a convenient choice for smaller households with limited space available.
An under sink water filter typically requires less maintenance than most other filtration methods, and is ideal for busy households where minimizing ongoing chores is a plus.
You turn on your faucet and that’s it – you get clean, filtered water immediately. There are no additional steps involved, like filling a jug and waiting for water to pass through its filter.
One under sink water filter can typically only be used for a single exit point. If you want to cover more faucets, you’ll often have to invest in additional systems, and the cost of that can add up very fast in a large households with many points to cover.
If you’re buying an under sink water filter with its own dedicated faucet, you’ll have to do some additional work during the installation, like drilling a hole through your countertop. This is something not everyone will be comfortable with, and may require the services of a specialist. That can add to the installation cost a bit, but usually the final price is still going to be manageable relative to the overall cost of the filter.
If you have any questions about how an under sink water filter works please don’t hesitate to leave a comment below!
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