AO Smith RO Filter System Under Sink Reverse Osmosis Installation

AO Smith RO Filter System Offers Pristine Drinking Water with Remineralization

Whole-house charcoal water filter systems are great at getting rid of taste and odor in water. When you’re ready to take it to the next level, reverse osmosis takes you there. The problem is that it’s so good at removing particles that it takes out some of the good stuff, too. The AO Smith RO Filter System has something a little special in mind—a remineralization process.

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AO Smith RO Filter System Key Features

Water Filtering at the Next Level

AO Smith lays claim as the first water filter system to combine three processes—reverse osmosis (RO), advanced selective filtering (Claryum), and remineralization.

The system starts with a carbon filter to remove chlorine taste and odor, mainly. Then it moves onto the reverse osmosis stage.

RO systems do a great job at removing and reducing some of the really nasty chemicals that may have trace levels in your water (even public water systems). Even though your local water regulations determine what safe levels are and regular testing ensures your water is safe, many of us don’t want even trace elements in there. Aside from chlorine, RO can nearly eliminate any remaining lead, mercury, fluoride, and other particles down to 1 micron in size.

After the RO filter, AO Smith adds a Claryum selective filtration system. This is an important step because RO doesn’t remove things like pesticides, herbicides, and VOCs (volatile organics). By the time your water moves through this filter, it’s as clean as it’s going to get.

AO Smith RO Filter System for Under Sink Installation AO-US-RO-4000

There are some things that the system won’t remove. The main ones are iron and micro-organisms, including bacteria (chlorine should kill any micro-organisms before the system removes it).

The downside is that the comprehensiveness of a system like this removes some good things, too. So the AO Smith RO Filter System wraps things up with a remineralization process. Among other things, it returns calcium, magnesium, and potassium to your water—elements critical to human body functions.

If you’re checking against National Science Foundation standards, it hit NSF 42, 53, 58, 401 + P473.

Installation

When you’re preparing for installation, keep in mind that the brushed nickel faucet that comes with the set isn’t a replacement for your current faucet. The system has a lower flow rate (1/2-gallon per minute) and it needs to ensure hot water doesn’t run through the system (90ºF max).

You need a two, three, or four-hole sink that gives you access to install that faucet. You might have to give up your soap dispenser or sprayer to make room if you only have a two-hole sink. It’s possible to drill a new 1-1/4″ hole, but be mindful of what material your sink is made of. Some materials are more forgiving than others.

This is going to be a more complex installation than we saw with AO Smith’s whole-house filter. If you’re not confident in your plumbing abilities, calling in some professional help might be the best route.

In the Kit

AO Smith RO Filter System—carbon, RO, Claryum, remineralizer
Filters for each stage
Storage tank
Brushed nickel faucet
All parts required for installation

Maintenance, Filter Replacement, and Model Numbers

There are three filters: a membrane filter cartridge (center), a carbon filter cartridge (AO-4000-CARBON), and a blue Claryum cartridge (AO-RO-RM-R). They recommend a carbon/Claryum filter change every 6 months. The membrane cartridge they recommend every 12 months. If you use less water, you can likely go much longer than that unless your water is particularly hard. Waterflow slows down as they get further along. AO Smith also recommends changing out the remineralizer (the small canister) every 12 months.

Price

The AO Smith RO Filter System runs $179 at Lowe’s with everything you need for installation, and we’ve seen it on sale for a little less. You can snag the carbon and Claryum filters as a set for $59.98 and a replacement RO membrane/remineralizer set for $89.98.

All told, you’re looking at $179 to get started, and $60 for your first replacement filters 6 months later. Then it’s roughly $210 per year in filter replacements after that. The system itself has a 2-year warranty.

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