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Availability:
In Stock.
Arrives
Monday, Oct 19
Features
- ONEFLOW PLUS SCALE PREVENTION SYSTEM: The Watts Premier OneFlow Plus Salt-Free Scale Prevention and Water Filtration System provides chemical-free scale reduction and protection. It converts hard minerals into soft particles, preventing build up inside pipes and does not add or remove anything from water, allowing useful minerals such as calcium, potassium, and magnesium to remain.
- HIGHLY EFFECTIVE: Rated to be the most effective with regard to scale prevention technology, this system includes one scale reduction cartridge good for up to 250,000 gallons or 3 years and one high-capacity 20-Micron carbon block water filter that removes chlorine taste and odor while reducing sediment and is good for up to 50,000 gallons - leading to great-tasting water at every tap in your household.
- USER-FRIENDLY DESIGN: This 10" x 18" x 10" (D x H x W) compact system is easily installed to the floor or wall using the included mounting bracket; simply connect the system to the main water supply before the water heater and avoid exposing it to freezing temperatures. Virtually maintenance-free, it also includes a pressure relief valve and multi-function tool for easy cartridge replacements.
- ENVIRONMENTALLY FRIENDLY: This system improves efficiency of all water heating devices and downstream plumbing components, improves equipment life, reduces energy consumption, and is a great alternative to standard water softener or other whole house water filter systems. It is environmentally friendly with no electricity or drain required and no waste water.
- THE PREMIER DIFFERENCE: Since our founding in 1989, Premier has been dedicated to the design, development, and marketing of high-quality water filtration systems that exceed industry standards. Following our Watts Water Technologies in 2001, our audience and influence have only expanded, solidifying Watts Premier as a trusted leader in the industry.
Description
OneFlow Plus Salt-Free Scale Reduction and Water Filtration Systems use a commercially trusted, physical water treatment technology to keep scale from forming on pipes and reducing appliance life, along with a high-capacity water filter to remove foul tastes, odors, and sediments for better tasting tap water. A single, compact unit with dual cartridges replaces a space-consuming water softening system and water filtration system — using no salt, chemicals, and electricity. OneFlow Plus is an intelligent scale solution and is a great salt-free alternative to water softening (ion exchange) or scale sequestering devices. OneFlow Plus system is certified by the Water Quality Association (WQA) to NSF/ANSI Standard 372 for lead free. The carbon block used in the OFPRFC carbon filter is certified to NSF/ANSI 42. Watts Water Technologies OneFlow Anti Scale Media is certified by the Water Quality Association (WQA) to NSF/ANSI Standard 61.
Specs & Other Info
| Specification | Details |
|---|---|
| Brand | Watts |
| Key Feature | Indicates when to replace the filter |
| Dimensions | 9.2"L x 9.2"W x 19.3"H |
| What's Included | Dispenser |
| Placement Type | Freestanding |
| Power Requirement | Corded Electric |
| Weight | 15 lbs |
| Model | OneFlow Plus |
| Min. Temperature Limit | 40°F |
| Max. Flow Rate | 10 GPM |
| Model Number | OFPSYS |
| Initial Release Date | June 14, 2016 |
| Origin | China |
| Popularity | #148,637 in Tools & Home Improvement, #1,991 in Water Filtration & Softeners |
| Customer Rating | 3.8 out of 5 stars (134 reviews) |
Frequently asked questions
The Watts OneFlow Plus system utilizes a unique scale prevention technology that transforms dissolved hardness minerals into harmless, inactive microscopic crystal particles. These particles stay suspended in the water and are easily passed through your plumbing system, preventing the build-up of scale and corrosion. It combines this technology with a high-capacity carbon filter for reducing chlorine taste and odor, as well as other contaminants, providing you with cleaner, softer water throughout your whole house.
No, one of the main advantages of the OneFlow Plus system over traditional water softeners is that it does not require the addition of salt or chemicals to operate. This makes it a more environmentally friendly and low-maintenance option for reducing scale and improving water quality in your home.
The life expectancy of the filters and scale reduction cartridge in your OneFlow Plus system depends on your water usage and the quality of your water. However, it is generally recommended to replace the carbon water filter every 6 to 12 months and the scale reduction cartridge every 2 to 3 years. Monitoring your water quality and pressure can help indicate when it's time for a replacement.
The OneFlow Plus system is designed for easy installation in most residential homes. It requires no electricity and can be installed on both municipal and well water supplies. However, for homes with very high hardness levels or specific water quality issues, additional pre-treatment may be necessary. It's always a good idea to test your water and consult with a professional installer to ensure the system will meet your needs.
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This is our summary and key points to consider based on customer reviews.
Users generally love this sleep sack for its quality, warmth, and the comfort it offers. It's a great transition tool from crib to toddler bed and has been well received for its durability even during the wash. However, some users have raised concerns about its sizing and the large size of the leg holes.
Pros
- 🌟 High-quality material and build
- 🔥 Provides good warmth and comfort
- 💦 Durable even after wash
- 👶 Works well for transition from crib to bed
Cons
- 📏 May run small in size
- 👣 The foot-holes are large and may ride up
- 🌞 Might be too warm for use in the summer
Should I Buy It?
Despite minor drawbacks such as size discrepancies, the positives far outweigh the negatives. The quality, comfort, and practicality of the sleep sack make it a worthwhile investment for any parent seeking to upgrade their child's sleepwear. Do consider your child's comfort and preference regarding warmth before buying.
Bought this in Dec of 2020 after I hauled away our old GE water softener (salt). The OneFlow fittings were a bit of a pain to match to our CPVC system, but I got it done. I also agree with another reviewer who said there should be shutoffs on each side of this to make maintenance easier. I put 'em in, and yes, maintenance is easy. =) I've changed the big/outer filter twice (early 22 & now), and the inner once (now). Both times the water between the housing and the big filter was the color of brewed tea (no smell, but still disturbing). However when I pulled up only the inner filter, the water was clear as could be. A few weeks ago we started to see some minor hard-water deposits on the shower heads, so I went ahead and changed both filters (and O-rings). For the inner filter, that's the first time since we put the system in. Now that it's changed, I fully expect another 3 years of not having to worry about hard-water deposits. I can't say it will work for you, but in our book, we've certainly found the system to be worth the money.
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Reviewed in the United States on January 9, 2024 by D. Spake
I installed the filter system this past week. Now it’s wait & see while the unit begins improving the quality of water in our house. I did the installation using a crimp tool, clamps, and a PEX cutter (that came in a kit) I found on Amazon. I locally sourced the Sharkbite clamp fittings including 6 elbows, 2 T’s, 3 ball valves, 2-1” female threaded adapters X ¾” Sharkbite Crimp fittings (I sourced these two parts on Amazon after searching 4 local hardware stores and having 0 luck finding them). I also needed 2-5’ sticks of 3/4” PEX tubing. I ended up with about 3’ of drop or unused pipe. I’m saving it for future use. I needed around 4 hours total time to attach the hanging bracket to the wall with 3” & 1 1/2” wood screws, cut the PEX into the desired lengths, connect the fittings and crimp the clamps. Cutting into the existing water line was the most white knuckle moment because thats the point of no return when you know you’re really committed to the project. Fortunately for me, I was able to tie in the filter system in a section of existing PEX rather than having to cut the copper tubing that comprises the majority of the plumbing pipe in my older home. After I restored the water pressure to the whole house i had NO LEAKS!!! I was ecstatic! Now we have to wait and see if the hard water scale is slowly reduced from pipes, faucets, toilets, and hot H2O tank, as Watts claims it will be. Time will tell!
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Reviewed in the United States on November 21, 2025 by horqua
I bought this in January 2020 and had a local plumber install it. Things were fine and water quality did seem better until this month. Now cracks have appeared above the inlet and outlet ports in the tank itself. The manufacturer Watts indicates that there is a 5 year warranty on the tank. When I called they said I had to go through Amazon since that is where I bought it. Now Amazon indicates the “window of support “ closed last year. I guess I’m just out of luck. Very disappointed in both Watts and Amazon on this.
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Reviewed in the United States on September 27, 2023 by Jim Witherell
We didn’t want an actual softener for myriad reasons but we needed a solution for the extremely hard water. After a week of research we settled in giving this a shot and have not been disappointed. Our house is new construction and I finally installed this filter after we’d been here for a month, and already fixture were accumulating scaling and we were running vinegar through the dishwasher. We saw that stop within a coyote days and while standing water that evaporate will leaves spots, those spots are more a dusty residue that easily wipes up. We are running the filter in sequence with an electromagnetic descaler (HQUA), which was installed simultaneously, so it is difficult to say how much effect is compounded by the joint treatment. The carbon filter does exactly what it’s supposed to. Tap water is now plenty satisfying to drink and the old chlorine odor is hardly present, if at all. Over all extremely satisfied with the installation process, the only difficulty was my inability to properly apply the silicone tape properly the first time to the brass threading.
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Reviewed in the United States on December 31, 2019 by Tim M.
Read the description, it does work as advertised. “Prevention”. But, in my case I was using it to replace a genuine salt style water softener. If your expectation is that you were going to use this product to replace the salt water softener, you will be disappointed. It does not match the spot reduction of a genuine salt system. Although it is way better than no system.
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Reviewed in the United States on November 8, 2017 by John Levitz
We purchased this product to eliminate a couple of water filtration and non-salt water conditioning. The unit is being used for wholehouse water filtering and water conditioning. Some of the internal parts are plastic and very flimsy. One part that directs water flow internally, broke with the first filter replacement. I have tried several times to obtain a replacement for the part to no avail. I would not purchase this unit for long term solutions to water treatment or filtering. The replacement filters are very expensive, with no solutions availed to you if a flimsy plastic part is broken. The only solution is to buy a new unit. A very expensive proposition.
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Reviewed in the United States on March 6, 2023 by Jonathan H.
One of these was in our new home when we moved in 2 years ago. We quickly realized it did not replaced a water softener by any means, and installed a new one of those, but kept using this for the whole house filtration after buying a new filter. That replacement filter lasted about a year and a half; we were alerted to how dirty it had become because the housing cracked - thank goodness we noticed the small leaking right away. As we could see how much we needed the extra filtration, we bought a whole new unit. After hours of installation frustration, my husband and father, who are REALLY experienced DIY with all things plumbing, finally just reused the fittings from the old unit to make this new one seal. Terrible for this much money that the parts don't wrok right.
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Reviewed in the United States on June 15, 2026 by BeJoyfulNow
I just finished installing this unit to replace a Colligan salt unit. I had problems with the threaded inlet/outlet adaptors leaking through the threads. I tried Teflon tape three times before using tfe paste which so far has fixed the problem. Other things to consider would be putting shutoff valves on both sides of the filter and a bypass system (if you have room) to bypass the filter and still have water to your house. The valve on the outlet side keeps your house plumbing system from draining back to the filter. Some people have noted the filter cost vrs salt costs. Our current salt price is over six dollars per bag. At two bags per month that is $432 for three years. Of course, there will be differences depending on water hardness and water usage. It might be helpful for some people if Watts could supply 3/4" inlet/outlet fittings instead of one inch. Many older homes have 3/4" piping. The new home we were living in in 2007 had one inch service lines.
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Reviewed in the United States on December 2, 2020 by Dan Proctor