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Defender Whole House Reverse Osmosis System
SKU:
224-DFWHRO-4000-PF
The Defender™ is a USA-made whole-house reverse osmosis system built for performance, longevity, and peace of mind—removing even the toughest contaminants and delivering clean, great-tasting water to every tap.
Subtotal:
$9,695.00
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Industrial-Grade Purity, Made for Home Use
Reverse osmosis is used in aerospace, biotech, and high-tech manufacturing. The Defender brings that same level of protection to your entire home by reducing TDS by up to 99% and removing thousands of harmful impurities.
Before
After
Take the Not-Water Out of Your Water
Everything that doesn’t belong—gone at 0.0001 microns
Carefully Assembled in the USA
Precision-built in America with better parts, better oversight, and better support
Engineered to Waste Less, Deliver More
High-efficiency RO with built-in recycle and blending functionality
Built to Outlast. Rated for Years, Not Months
Long-life membranes, stainless steel, and smart design. Built for the long haul
Benefits You'll Love: The Power of Whole Home Reverse Osmosis
Unmatched Water Quality
The Defender system can drastically reduce chemicals, bacteria, and heavy metals throughout your home. You’ll have peace of mind knowing your water is cleaner and safer from every tap.
Healthier, Better-Tasting Water
Your water will taste fresh and pure, free from unpleasant odors and flavors. Enjoy better-tasting coffee, tea, and meals without needing bottled water.
Protects Your Home and Appliances
This system reduces wear on your pipes and appliances caused by hard water and contaminants, saving you money on repairs and extending the life of your home’s infrastructure.
Complete Well Water Protection
Ideal for private wells, this system offers multi-layered protection against sediment, chemicals, and pathogens, ensuring safe, usable water throughout your home.
No Bottled Water Needed
Skip the cost, waste, and hassle. Defender delivers better-than-bottled quality from every faucet—eliminating the need for single-use plastics or countertop filters.
Laundry That Feels (and Smells) Better
RO water prevents mineral buildup in fabrics, so clothes and linens stay brighter, softer, and free from musty odors.
The Defender Whole House RO - A Complete Solution
With pre-treatment options, ultraviolet disinfection, storage, and water delivery, this product is customizable to meet your unique water quality needs.
Installation Guide
(Optional) Backwashing Pre-Filter for De-Chlorination
Inlet Water Supply
Lockout Relay; prevents backwash during system operation
Anti-Scalant Injection Connections
Lockout Relay; prevents backwash during system operation
RO system power, 220v 1PH 20A
Tank Float connections to turn the system on and off
Booster pump, to deliver water pressure to home or business
110v outlet for power to UV disinfection lamp and SCALA delivery
pump
Tank isolation valve
Concentrate discharge from RO system
Clean water tank-fill line from RO system
Atmospheric holding tank, for storing purified water (multiple size
options available)
Pressurized purified water returning to home or business
American Craftsmanship
Every detail of a Defender Whole-House Reverse Osmosis System is built with longevity and reliability in mind. Superior components and quality control add up to a system that you can rely on.
Industrial Heavy Duty Pumps (Available Options)
Built to Last
We use stainless steel reinforced fittings, a multi-stage stainless steel booster pump, and the highest quality stainless steel valves to make sure you always have clean, high-quality water.
Reverse Osmosis System
Comparison
| Product Features | Defender Whole House RO | The Other Guys |
|---|---|---|
| Pump | Multi-Stage Stainless Steel Booster | Cast-Iron Rotary Vane |
| High-Pressure Fittings | Stainless Steel Reinforced PVC | PVC |
| Valves | Stainless Steel | PVC/Brass |
| Warranty | 2-Year "Bumper-to-Bumper" | 1 Year Limited |
| Tech Support | Lifetime Expert Tech Support | Outsources Limited Tech Support |
Pre-Treatment: What Is Needed For RO Success
A reverse osmosis system can clean up a mud puddle. However, the question becomes... for how long? With proper pre-treatment, a reverse osmosis system will give you years of reliable performance and outstanding water quality.
For Homes With a Private Well
No two wells produce the same water. The chemistry can vary dramatically—from iron, manganese, and sulfur to bacteria, nitrates, and PFAS. That’s why US Water Systems follows the principle: measure twice, cut once. Before recommending a Defender™ system—or any solution—we strongly advise starting with a laboratory-grade water analysis. It’s the most responsible first step toward solving water quality issues the right way.
A Smart First Step—At No Risk to You
The cost of the Waterlogix™ test kit is fully credited toward any recommended system purchase. That means your lab-grade water analysis is essentially free when you’re ready to move forward—ensuring our solution is right the first time and allowing us to stand behind its performance with confidence.
For Homes That Pay A Water Bill
Water from a municipal source has 3 primary and predictable waterborne contaminants that would be addressed prior to entering your RO system. These contaminants are sediment, chemicals such as chlorine, and limescale.
BodyGaurd Plus - Dechlorination System
- Protects the Reverse Osmosis Membranes
- Highest Quality Coconut Shell Carbon
- Bluetooth Operation and Monitoring
- 10-Year Warranty On Valve and Electronics
- Reduces Disinfection Byproducts, Chemicals, and Many Other Contaminants
Behind the Scenes: Membranes
Permeate Collection Tube Brine
Seal Feed Water Concentrate Water
Purification
Network RO Membrane Purified
Water
Pre-treated water is pumped into the RO membrane at about 150 PSI
As the water moves through the wound passages in the membrane, it’s separated into two streams: Permeate = Good Water Concentrate = Waste Water
The treated water (Permeate) then flows out of the membrane through the collection tube and into the storage tank
A portion of the wastewater (Concentrate) can be recycled back to the input to improve recovery, and the small portion remaining flows harmlessly down the drain
US Water Systems’ Waterlogix ™ 4 x 40" High-Efficiency Membranes allow for industry-leading water recovery and total dissolved solids reduction
Ultimate Filtration: Eliminating PFOA/PFAS and Beyond
| Contaminant | Reduction | Contaminant | Reduction |
|---|---|---|---|
| Algae | 99.99% | Mercury | 98.00% |
| Aluminium | 98.00% | Mold | 99.99% |
| Amoebic Cyst | 99.99% | Nickel | 95.00% |
Simplified System Flow Diagrams
System Installation Requirements
Still Have Questions?
Overall rating: 4.638889 / 5 from 36 reviews.
AI Generated Review Summary
The Defender Whole House Reverse Osmosis System offers industrial-grade water purification, reducing TDS by up to 99% and removing harmful impurities. Customers appreciate its easy installation, high-quality components, and the significant improvement in water taste and quality. This system is ideal for both municipal and well water, providing long-lasting, reliable performance.
Summary topics
- Ease of Installation (28%): Many customers loved the easy installation process of the product, praising its ease of use and fantastic customer service.
- System Performance (60%): A significant amount of customers expressed satisfaction with the system, praising its performance and ease of installation.
- Water Purification Quality (60%): In general, customers found the water purification system to be the best they have ever used.
Review topics: ["support","customer service","staff","system","service","quality","results","water","confidence","instructions","installation","issues","plumber","decision","pressure","call","components","solution","guys","flushing","works","salt","tank","line","smell","choice","tds","package"].
Review highlights
- "Our mission was to obtain the best water purification system possible in our quest for purified water for our house." —
- "Great system and easy install." —
- "We've been very happy with our water system and with the support provided by the US Water team." —
Reviews
Unfortunately, I cannot recommend this system.
"I purchased the Defender Whole House Reverse Osmosis System last fall, along with the anti-scalant pre-treatment and remineralization post-treatment systems. Between the $14,500 purchase price and the electrical, plumbing, drain, drywall, painting, and installation work required, this was quite expensive and time consuming to setup. At the time, I felt the end result would be worth it. The problems began before the system was even operational. The holding tank arrived with musty-smelling water inside and had to be sanitized. Many of the fittings and components required simply to connect the system to itself were also missing. Some were specialty parts that were difficult to source locally. By the time I purchased everything needed, I had spent roughly another $1,000 and lost several weeks of time. I was told some parts were missing because I had ordered a custom-size holding tank, although not all of the missing components appeared to be related to the tank. Once installed, I was surprised by how loud the RO pump is. When the system is producing water, it is loud enough that having a conversation near the equipment is unpleasant. We can even hear it from our living room through an insulated shear wall. The reliability problems were much more concerning. A failed solenoid caused the system to continuously produce and discharge water even when the house was not using any. I initially called a plumber to check the house for leaks because I did not realize the RO system itself was malfunctioning. Because I also had the remineralization system, the repeated cycling apparently continued adding treatment material to the finished water. When I tested the water, the pH was beyond the top of my test range at 10+. At one point, the system also consumed roughly three months' worth of anti-scalant in only a week or two. I later found brown slime on rubber components and tubing inside the finished-water holding tank. I cleaned the tank and replaced the failed solenoid, but the solenoid subsequently failed again. When I later inspected the tank, the brown material had returned, and this time the water had a strong rotten-egg odor that filled the whole garage. At that point, I simply lost confidence in using the water for drinking or bathing. Even if another repair makes the system operate correctly today, I am no longer comfortable wondering whether another malfunction may be occurring without my knowledge. The most frustrating part of writing this review is that US Water Systems' customer support has actually been excellent. Their team has been responsive, helpful, and has even assisted me after hours. I genuinely appreciate the people who have tried to help. Unfortunately, good customer support cannot overcome my experience with the system itself. It is less than a year old, and I have decided to remove it and install a different water-treatment system. I will be able to reuse the UV equipment and some of the infrastructure, but I expect to lose the majority of the $14,500 system cost, along with approximately another $3,000–$5,000 in installation and related expenses. For a product purchased specifically to provide clean, trustworthy water throughout our home, this experience has not provided an acceptable level of reliability or confidence."
Don't buy if you live in a rural area. . . .
"I REALLY regret paying over $11,000 for a whole house RO Defender system from US Water Systems. I live in a rural area in a small town with poor public water quality (very hard) and gravity-fed water pressure. The RO system requires a minimum operating pressure of 50-60 PSI to function properly and the plumbers who hooked up our system failed to mention I'd need a pressure boost system to maintain the operating pressure needed to have the unit run properly. You get ZERO support from US Water Systems after you purchase a unit like this. There's no local plumbers who know, or are interested in understanding, how the system is supposed to work, so if you purchase one of these, and live in an area where you're likely to really need one, you need to be aware of what your signing yourself up for. You will be the "expert" protecting your $11,000 investment. The biggest issue I have with this whole system though is the pre-filter design. It's the most common maintenance aspect of the system. The pre-filter is huge and it's impossible to change without making a huge mess and/or damaging the system, as we unfortunately did on one occasion. The pre-filter housing is close to 3 feet long and is full of pressurized water when you have to change the filter. I've not weighed it but it's probably close to 50 pounds of unstable weight you have to spin off the fitting, try not to drop, then use another hand to manually pull the paper filter off the interior fitting so the whole pre-filter assembly can be pulled free from the unit. It's the worst F-ING design flaw imaginable for the most common maintenance procedure on this system. My 18 year old son accidentally dropped a full assembly and it broke the inlet water fitting clean-off because that was designed to be directly under this stupidly designed pre-filter assembly. There's very little room to get the filter wrench into the unit to loosen the pre-filter and as stated earlier, it is IMPOSSIBLE to get the entire assembly removed from the unit without creating a huge mess. You have to tilt the pre-filter housing to free it from the interior of the unit so your dumping at least a quart of water out on your floor every, single, time. A simple fix would have been to place the prefilter in a more accessible location OUTSIDE the main unit of the RO system and put a F-ING pressure relief valve on the pre-filter housing so users can relieve system pressure, making it easier to loosen the pre-filter assembly, and drain all the water weight from the assembly into a bucket to reduce the mess and make it easier for an average strength person to change the F-ING thing every 2-3 months. This system may be great for people who in more populated areas where qualified plumbers are readily available but for small towns in more isolated areas should contact the most reputable plumber in the area they live in BEFORE buying a system like this. Tell them what you're interested in and let them tell you what they would recommend based on your water quality issues. Thought I was smart for doing all this research and trusting the reviews many other people have made on this company and this RO Defender system. . . I learned the hard way on this one. If you are still in love with the idea of whole house RO and like this system, call the company and ask who they have as a certified plumber in your area who can do the installation first, then call that plumber to make sure they are still in business and are willing to instal one of these systems and help keep it running when you run into problems. . . which you will."
I’m very pleased and impressed
"I’m very pleased and impressed with this RO system took my total TDS of 1760 down to 22. Customer service was very helpful and friendly to talk with. Thank you US Water!"
Just installed and water quality is superior
"I replaced the Grunfos system with this system. It is not cheap, but the water quality is 1000% better than the previous system. The first thing I noticed was taste, better than bottled water. I have the house cleaned every two weeks and the toilets would get a black slime build up in the bowl and now they are spotless. I have an irrigation system for the lawn and garden and water recovery is instantaneous. The system I replaced would use 2/3 of 150 gallon tank and would take 4 hours to refill. More ideal construction and all filters, pumps and connections located in one system other than a tank attached separately that supplies a chemical agent to keep the reverse osmosis filters from buildup. Well water is located on a peninsula surrounded by Leadenwah creek and marsh. Salt content in the well water is high, but clear. No salty taste in the treated water after it’s processed. The well water is diverted to a salt water pool and it’s clean with weekly pool service."
The Best!!!! company I have ever dealt with
"Wow was I lucky to find US water. My water was not the best and was testing with a lot of arseni, iron, magnesium, and a few other things. I had water treatment installers telling me my water was so bad that I should go with a bigger company and other bigger companies giving me quotes of $40,000 for a whole home system which in my mind was outrageous. That’s when I found US water system and began the process of finding out what my best solution was. From the moment I sent them over my test results they were able to build me a whole home treatment system based on my water quality and for less than half the amount I was getting quotes for. Shipping was fantastic. I got an email notice stating that it was going out and received it within four days delivered to my door by a shipping company. When the components arrived at first, I was a little overwhelmed by all the boxes, but after opening them all up and contacting their Help support line, I was able to decipher everything in detail how things worked. The customer service and their technical support that US water system supplies was amazing is all I can say anytime I had a question I picked up the phone and there was always someone there to answer it within minutes. There was no waiting on hold for 20 minutes or 30 minutes. It was like they were there just for me. I did hire a plumber because I wanted it to look nice and neat, but this is definitely a system for a homeowner with some handyman experience would be able to install. We are finally up and running and the water is so clean and safe to drink. It’s amazing how this system works. We were getting all kinds of spots on our dishes from the buildup of the heavy metals and now it’s just sparkling like a diamond ring, even after install and getting everything up and running, I am still able to give them a call and they still are more than happy to assist me when it comes to dialing the pH in and all the products that are required from my system. Oh, and did I mention that the helpline is also open on Saturdays and holiday weekends. Amazing Company !!!!"
Defender 4000
"I have had my defender 4000 US Water Systems RO system in place now for just over one year. I had it professionally installed by a water specialist because I was not in the area when the project needed to be completed. However, after reviewing the project and the explicit instructions provided by US Water Systems I decided that it was definitely a DIY project that I could’ve handled myself. I have since called the technical support line a couple of times simply to see what I might do to keep my system, running smoothly and answer a few questions regarding water quality, and such, both times I called technical support. I spoke with John Shepard he was extremely helpful and easy to talk with. I would highly recommend the system to anyone looking to have quality water throughout their entire home."
Over 3000 TDS to 10
"After getting a detailed water test by a lab I received levels that were not fit to consume. My water tested out above 3000 ppm TDS, extremely high in Sulfates. The inside of my dishwasher looked like it was painted white. After installing a Defender Whole House RO 4000 filter, my TDS dropped to 9 ppm. I have been running it for 1 1/2 years and my TDS number is still 10 ppm. The dishwasher looked brand new after a few washes. way beyond any expectation I had. Great customer service too. Thank you !!"
Spectacular
"Beat my expectations, really. Reduced TDS from 500 to 15 on city water in San Diego."
Incredible system
"The staff was great every time I called with questions. And the system is great. I’m only sad that I waitied this long to install a reverse osmosis whole house system."
Q&A
- Can I use my HSA to pay for an RO system?
- Short answer: usually no—not unless it’s prescribed to treat a specific medical condition. Recommend you check with your provider.
- Is treatment needed after the system to prevent corrosion of the home plumbing system?
- Yes — treatment after the Defender whole-house RO system is recommended unless your home’s plumbing is entirely corrosion‑resistant (such as PEX, CPVC, PVC, or stainless steel). RO water is low in minerals and can have a lower pH, which makes it more aggressive toward copper, brass, and lead‑soldered joints. Without post‑treatment, this can lead to pinhole leaks and other corrosion issues over time. The Defender’s optional pH boost/rematerialization upgrade is designed to raise pH, add buffering minerals, and help protect metal plumbing. If your home uses only corrosion‑resistant piping, post‑treatment isn’t strictly necessary, but it can still improve taste and help stabilize water chemistry.
- What is the atmospheric holding tank made of? Is is steel or plastic?
- The atmospheric tank that is included is made of polyethylene.
- If I want to increase my GPD, can I install and additional membrane on my Defender? If so, what parts would I need and is there an installation document/manual available?
- Yes this can be done. Please contact Technical Support @ 800-390-5936 and one of the techs can give you part numbers and instructions.
- Do I still need a water softener with this system?
- Hardness must be treated feeding an RO system. While a softener will work, we prefer to use an anti-scalent injection as it is more efficient and costs less in the long run.
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