What Is Reverse Osmosis Water? Your Comprehensive Guide

November 21, 2023


how does reverse osmosis work infographic

Reverse osmosis water is demineralized or deionized water. Before becoming clean water, regular water goes through a reverse osmosis system that uses a semi-permeable membrane and force to create cleaner water.

So, what is reverse osmosis water? It’s cleaner water that is more appealing for drinking, cooking, and other uses. If you’re still unsure if a reverse osmosis (also known as RO) system is suitable for your home, continue reading to learn how it works, the benefits of this type of water purification system, and everything else you need to know to make an informed decision.

If you’re considering making the switch, the experts at YES! can answer any additional questions you may have and take care of installing the system for you.

The Reverse Osmosis Process

What is a reverse osmosis water system, and how does it work?

Reverse osmosis systems clean water by forcing the liquid and any contaminants within it through a semi-permeable membrane. The term “semi-permeable membrane” refers to a filter with tiny holes, allowing water to pass through easily while leaving contaminants behind.

Think of it like how a screen window or door lets fresh air in while keeping bugs out because the bugs are larger than the spaces within the mesh screen. This type of filter eliminates 95% of contaminants, such as solid substances, foreign contaminants, large molecules, and minerals from the water.

Reverse osmosis differs from other water purification methods because it doesn’t need an outside energy source, relying on high force or pressure. That force allows water to pass through easily while keeping contaminants out.

The Parts of a Reverse Osmosis System

The best way to understand how a reverse osmosis system works is to review each part of the system and what it does. A typical system includes the following:

  • Water supply connector
  • Sediment pre-filter
  • Carbon pre-filter
  • RO filter
  • Carbon post-filter
  • Water storage tank
  • Faucet and pressure regulators
  • Wastewater disposal system

Water Supply Connector

Also known as a feed water supply adapter, this part of the RO system connects to the system that supplies water to the house. This component provides water to the RO system to undergo the purification process.

Water that goes into an RO system is known as feed water. After it has gone through the process, it’s called permeate water.

Sediment Pre-Filter

The feed water then goes into the sediment pre-filter, which is the first step in filtration. It ensures that the semi-permeable membrane can get rid of as many unseen contaminants as possible, as the filter is designed to catch larger bits of debris.

Smaller pieces of debris can move through this filter but will get caught in the subsequent layers of filtration. This step also protects the membrane from damage caused by large pieces of debris.

Carbon Pre-Filter

The next filter removes chlorine and chloramine from the water, which can also damage the RO membrane. These chemicals can result in oxidation and degradation of the membrane. Prevention is essential because damage from these chemicals cannot be reversed.

Auto Shut-Off Valve

The auto shut-off valve can help save water by cutting off the supply when the RO pressurized tank is two-thirds full. Once the level drops to one-third of the tank’s capacity, the valve will allow more water in.

RO Filter

Here’s where reverse osmosis occurs—the tiniest contaminants are separated from the liquid, creating fresher water.

Check Valve

Now that the permeate water has been created, the check valve prevents the liquid from going backward into the membrane. This step prevents contamination and protects the membrane from damage.

Carbon Post-Filter

As the permeate water moves through the carbon post-filter, any odd tastes or smells are removed as a final step before it enters the storage tank.

Water Storage Tank

A good RO system comes with a storage tank because the RO process takes time. A storage tank makes it much easier to access fresh water when needed rather than waiting for all the water needed to go through the process on demand.

When you turn the faucet to fill a glass, it will take a few minutes to fill up if you have to start the process from scratch.

Wastewater Disposal System

The membrane doesn’t clean all water that goes through it—instead, some water remains to house the contaminants. In the system, this liquid is called wastewater. An RO system should have a built-in way to get rid of this water, whether draining it or recycling it for use during the next cycle of reverse osmosis.

Faucet

Now that all contaminants have been removed from the water, you can access it with a faucet directly connected to the RO system.

Problems That Can Occur in a Reverse Osmosis System

Several issues can cause your RO system to perform poorly. If you notice that your system is experiencing issues, make sure to contact your local plumber to help you diagnose and resolve the problem and restore your access to fresh water.

A few of the most common issues impacting reverse osmosis systems include:

Chemical Damage

As mentioned, chemicals like chlorine or chloramines can damage the RO membrane. Essentially, these substances will cause chemical burns to the membrane, creating holes. This damage will weaken the membrane, allowing more contaminants to get through and eventually leading to breakage.

Fouling

Fouling is another word for when the membrane gets plugged up. This blockage occurs when contaminants build up on it. When the RO membrane is plugged, nothing can get through it.

Since the membrane has small holes, it doesn’t take much to plug it. This problem is difficult to diagnose because the contaminants are small enough to be invisible to the naked eye yet large enough to cause problems. It’s essential to contact an experienced professional to look at your system when it’s not working correctly.

Mechanical Damage

Because an RO system has so many working parts, mechanical damage is a common problem. Mechanical damage can wreak havoc on the entire system, whether it’s a prefilter failing or excessive water pressure.

Scaling

Various inorganic materials can build up throughout an RO system, causing scaling, or a deposit of minerals on the membrane. Scaling will put additional strain on the system’s function and may cause blockages in the membrane’s holes, resulting in the need for increased water pressure. Scaling also impacts the cleanliness of the water, even after going through the entire process.

What Types of Reverse Osmosis Systems Are Available?

The two main types of reverse osmosis systems are distinguished by the kind of membrane they use. As a quick refresher, a membrane works as a filter to stop contaminants from remaining in your drinking water.

The two different types of membranes are called Thin Film Composite (TFC) and Cellulose Triacetate (CTA). The main difference between the two is how much chlorine each can handle.

A TFC membrane is only able to filter water that’s already chlorine-free. If chlorine is present in the liquid, the membrane stops working. However, when used with water free from chlorine, the membrane is more effective at eliminating contaminants than a CTA membrane. Depending on the system's needs, the TFC membrane can have up to two additional layers.

By contrast, a CTA membrane can handle chlorinated water. However, this membrane may be more susceptible to bacterial damage. It is a paper byproduct bonded to a synthetic membrane.

Installation Location Types

Various RO systems also differ based on where they’re installed. Options include countertop and under-the-sink systems.

A countertop RO system is a free-standing unit that can sit alongside other household kitchen appliances on the counter. An under-the-sink system is connected to the kitchen sink, nestled below it among its plumbing components.

What Does Reverse Osmosis Eliminate?

At this point, you might wonder what reverse osmosis gets rid of in your water. After all, anyone can claim cleaner water with a purification system. The reverse osmosis process specifically targets and gets rid of the following contaminants:

  • Arsenic
  • Bacteria
  • Chlorine
  • Copper
  • Fluoride
  • Herbicides
  • Ions
  • Lead
  • Nitrate
  • Pesticides
  • Protozoa
  • Sodium
  • Sediment
  • Viruses

What Are the Benefits of Reverse Osmosis?

Although other forms of water filtration are available on the market, it’s helpful to understand the pros and cons of reverse osmosis. The following are some of the key advantages of this type of system.

Access to Clean Water

As mentioned, reverse osmosis water systems create clean water for you to use for drinking, food preparation, and other needs. The average RO system can eliminate 95% of contaminants, and some more powerful units can get rid of even more.

Makes Water Taste Better

Reverse osmosis water tastes better because the RO system removes anything that can create a bad taste or smell. You might think water has no taste, but you'll understand the difference once you have fresh, clean water. You may also notice a difference in the food you make.

Call 844-216-9300 to get an RO system installed in your home so you can taste the difference.

Better Efficiency

A reverse osmosis system is more efficient than most other water filtration systems. The efficiency directly relates to the number of contaminants the system gets rid of and the energy used. Unlike other units that rely on electricity or thermal energy, an RO uses pressure.

Another additional efficiency tool is the auto turn-off valve. This component ensures that the storage tank doesn’t get too full and prevents the system from running constantly. This feature can result in lower energy bills and a decreased carbon footprint.

Gets Rid of Sodium

A water softener cannot remove sodium from the liquid, but a reverse osmosis system can. Since sodium directly relates to many health issues, choosing a system that can eliminate it when necessary is vital. As the EPA points out, sodium in drinking water can be dangerous for those who follow salt-reduced diets to manage various health conditions like kidney problems or heart issues.

Additionally, water high in sodium becomes more corrosive, increasing the risk of damage to the pipes, pumps, water heaters, and other metal parts within your home. This damage will lead to expensive repairs or replacements.

Better for the Environment

Possibly the greatest benefit to an at-home reverse osmosis system is that it uses the same process as bottled water manufacturers, so you can be sure your drinking water is of the highest quality. You can then avoid purchasing plastic bottles, which benefits both the environment and your wallet.

The concern about plastic is so great that the UN is encouraging people to reduce their plastic use. In 2021, global bottled water sales reached 350 billion liters. You can help reduce this number by investing in a reverse osmosis system for your household.

Easy to Maintain

Reverse osmosis systems are easy to maintain, only requiring their filters to be changed every six to nine months. You can replace these filters yourself or contact a professional to help out.

Doesn’t Take Up a Lot of Space

A reverse osmosis system can be personalized to fit your home or kitchen. While exact sizing will depend on the system you choose, the equipment is typically small enough to fit under a sink or sit on a countertop without taking over the space. A reverse osmosis system under the sink is the perfect solution when a home doesn't have much extra room.

Call 844-216-9300 to get your reverse osmosis water system installed today!

Cons of a Reverse Osmosis Water System

No water system is perfect, and there are a few disadvantages to a reverse osmosis system.

Wasted Byproduct

Because a reverse osmosis system doesn’t use electricity, relying instead on force, it leaves contaminated water behind. While the system isn’t incredibly wasteful, it’s important to note that it will leave behind some unusable water.

Needs Maintenance

Due to the delicate nature of the membrane, an RO system will need occasional maintenance as the membrane gets plugged up or damaged. You can have one of our skilled experts handle your system’s maintenance needs by calling YES! at 844-216-9300.

Takes Time

Most RO systems include a storage tank because the reverse osmosis process takes time. Depending on how much water you use, or if you don’t have a storage tank, you may have to wait for the liquid to go through the process.

How Is Reverse Osmosis Installed?

Each installation process will differ based on various factors. These may include the type of plumbing system in your home, your selected RO system, and the space available.

However, most installation jobs include the following steps:

  1. Turning off or disconnecting running water from the sink (if the RO system is getting attached to the plumbing)
  2. Taking note of the materials of the plumbing system (a different method will be used if the components are metal vs. ceramic)
  3. Mounting the RO faucet
  4. Mounting the stop valve
  5. Installing the drain saddle valve
  6. Placing the original plumbing parts back in their proper places
  7. Installing the cartridge filter
  8. Installing the RO system
  9. Adding the supply tank
  10. Adding any other tubing needed
  11. Testing the system
  12. Diagnosing and fixing any problems

It may sound easy, but anything involving plumbing can be complicated. Investing in professional service for any type of plumbing work is always worthwhile. To ensure you don’t have a significant, wet problem on your hand, have a skilled technician install your reverse osmosis system.

YES! can help with that. Call 844-216-9300 today!

Drink Cleaner Water Today

You deserve clean drinking water in your home; a reverse osmosis system can make it happen. With minimal effort, you can enjoy access to water free from contaminants every time you turn the faucet.

If you have questions about the benefits, cost, special offers, or installation of a reverse osmosis system, contact the experts! Give your local plumbing professionals a call at 844-216-9300.

FAQ

Still have questions about what a reverse osmosis water system is? We’ve answered some of the most commonly asked questions below.

What Are the Benefits of Drinking Reverse Osmosis Water?

Drinking reverse osmosis water has many benefits, including:

  • Improved cleanliness
  • No bad tastes or odors
  • Enhanced efficiency in the cleaning process
  • No sodium

You can also enjoy the benefits of using reverse osmosis water when preparing food, cleaning, and handling other household tasks.

Is Reverse Osmosis Better than Drinking Water?

Yes, reverse osmosis water is better than typical drinking water that comes through the faucet. This is because a RO system can get rid of a variety of contaminants found in traditional tap water.

What Are the Pros and Cons of Drinking Reverse Osmosis Water?

The advantages of drinking reverse osmosis water include improved cleanliness and better taste. Not only will those benefits encourage you to drink more water, but they can also make the food you make taste better.

When you become used to tap water, it may take time to get used to the taste of the water that moves through the reverse osmosis system. Additionally, eliminating healthy minerals is a con of the RO process. But you can get the same minerals from other aspects of your diet, meaning your body won’t miss out.

Is It Better to Drink Tap Water or Reverse Osmosis Water?

Drinking reverse osmosis water over tap water is better because the RO process results in cleaner drinking water. However, this fact doesn’t mean tap water is dirty—it also goes through a purification process. The process is just not as detailed as a reverse osmosis system. An RO system is also a better alternative to bottled water as it has a lower environmental impact.

What Is the Process of Reverse Osmosis?

We’ve already covered how the entire reverse osmosis process works in detail. But a brief summary is that, through force, a reverse osmosis system pushes water through a filter. The holes in the filter are small enough that contaminants can’t get in, but water can get through—so one side of the filter has contaminants, and the other is clean.

What Are the Stages of Reverse Osmosis?

Depending on the type of reverse osmosis system you have, water may go through up to five stages.

A three-stage filtration system includes: 

  • A sediment pre-filter to get rid of debris
  • A carbon pre-filter to get rid of chlorine
  • An RO membrane

A four-stage filtration system has:

  • A sediment pre-filter
  • A carbon pre-filter
  • An RO membrane
  • A carbon post-filter to get rid of smells

A five-stage filtration system includes: 

  • A sediment pre-filter
  • A carbon pre-filter
  • A second carbon pre-filter
  • An RO membrane
  • A carbon post-filter

How Do Reverse Osmosis Systems Work?

Unlike other water systems that rely on electricity or other power sources, reverse osmosis only uses pressure. The system forces water through tiny holes to keep contaminants on one side, separate from the clean water you drink.

Does Reverse Osmosis Really Purify Water?

Yes, a reverse osmosis system really purifies water. The CDC states that reverse osmosis systems can get rid of:

  • Protozoa, like Cryptosporidium, Giardia
  • Bacteria, like Salmonella and E. coli
  • Viruses, like Hepatitis A and Norovirus
  • Chemical contaminants and minerals

Last Updated: March 18, 2024