Under-Sink Non-Electric RO System - U01

I bought the U01 for our camping trips, where the water often has a funny smell or taste. This compact gravity filter gives me real reassurance that what we're drinking is clean.
What makes it different: No big, bulky water tank �� just two stainless steel chambers. You pour water in the top, gravity pulls it through the carbon filters into the bottom. Such a simple design means less to go wrong, and the water genuinely tastes cleaner and better.
What's in the box: Everything needed �� main container, gravity-fed top, lid with handle, stainless steel spigot, two carbon filters, plus plugs if you want to run just one filter, and a silicone ring to stop it slipping.
Setup: Under 10 minutes and very straightforward. Just rinse the filters before first use. One tip: check you have enough washers to seal everything leak-free �� I needed a couple of extras.
[Photo 1: Unboxing / parts]
[Photo 2: Assembled unit in use]
Daily use: Holds about 1.5 gallons at a time �� perfect for one or two people, though you'll refill it more often with a larger family. The taste difference is immediate; I now run even my fridge-filtered water through it. It's small enough to fit under a cabinet and easy to take camping.
Honest drawbacks: No water-level gauge on the outside, and no stand included �� I set mine on the edge of a shelf, or you can prop a book under it.
Bottom line: Food-grade 304 stainless steel, quality build without the big-name price. If you want simple, clean-tasting water, this is it.

3/8�� compression fitting is not included. It looks similar but the included parts ��G3/8�� does not fit to the standard US faucet adapter.
You will have to order ��3/8�� compression male �� 3/8�� compression female �� 1/4�� quick connect�� separately by yourself.

This RO system is seriously impressive. You can tell right away it’s been thoughtfully designed—from the layout to the included components. It comes as a very complete package, including the faucet, so you’re not scrambling to buy extra parts mid-install.

The tankless design keeps everything compact and clean under the sink, and the system runs ultra-quiet, which is a huge plus. The real-time TDS display and pressure gauge are great touches—they make it easy to see exactly what’s going on instead of just hoping everything is working correctly.

Water flow is strong for an RO system, and overall it just feels convenient and modern compared to older setups. If you’re looking for a high-quality, all-in-one filtration system that’s easy to live with day-to-day, this is a great choice.

This Purewell Non-Electric Tankless Reverse Osmosis Water Filtration System has been a phenomenal addition to our home. While installation had a minor hiccup, resolved by finding a helpful video clip right on the listing page that cleared up the one detail I was stuck on, plus needing a separate T-adapter, the rest has been smooth sailing.
The benefits are undeniable. It doesn't require electricity, operates silently, and has no bulky tank taking up space. It dramatically improves water taste while effectively removing heavy metals, hardness, and various toxic contaminants. We use this purified water for everything: drinking, cooking, coffee, washing produce, and for our pets.
Maintenance is straightforward with a simple two-filter set (one replaced every 6 months and the other annually), making upkeep manageable. If you want pristine, refreshing water without the noise or electricity of traditional RO systems, this unit is an absolute winner. Highly recommended!

When I set up the system I followed the clear instructions and a short video. The quick?connect fittings meant I only needed a drill and a small wrench to finish the job. The tankless design saved space and the lack of an electric pump eliminated any noise or safety worries. The 7?stage filtration removed most of the dissolved solids and contaminants, and the built?in TDS display let me see the water quality in real time. I was impressed by the 800?gallon per day capacity and the ability to fill a cup in about five seconds, which is much faster than my old filter unit. The sturdy construction feels solid and the pressure gauge on the cap helps me monitor performance.

The unit is taller than it looks in the pictures, so I had to make sure there was enough clearance in my cabinet. Because the system does not use a booster pump, the flow can slow a little when multiple taps are on at once, but it is still adequate for normal use. Overall the Purewell U01 delivers clean, fast water with a quiet, compact design, and the few minor considerations are easy to manage.

This system delivers filtered water quickly without the bulky storage tank found in many traditional reverse osmosis systems. The real-time TDS display and pressure gauge make monitoring performance easy, while the high flow rate helps eliminate the waiting that often comes with smaller filtration systems.

Water quality improved noticeably, operation remained quiet, and the overall design feels thoughtfully engineered. The installation requires some planning, but once operational, it performs exceptionally well. For households looking for a premium filtration solution, it checks nearly every box.

I must say: this is a very innovative, tankless RO system, and I was glad to discover it on Amazon since I have a near obsession with RO water filtration systems. I especially appreciate the continuing improvements in overall performance and space saving designs. And this is where this system excels. I can also report that, I have had very good response and assistance from Purewell customer service when corresponding with them via their website and email.

Here's what I like about this system:
? It truly is very compact, taking up very little space under the sink. I��ve installed other tankless systems, and with the exception of the system height, this one is the most compact yet.
? Installation is easy; just follow the simple instructions within the manual provided or the informative video on Amazon. The tubing ports are also clearly marked, as seen in my pictures. Filters are also very easy to replace��no fumbling around with hard to reach and remove canisters or messing with O-rings.
? It has an indicator for TDS performance.
? It is SGS tested to NSF/ANSI 58 standards for reverse osmosis systems, ensuring the materials, design, construction, and performance can effectively and safely remove contaminants and reduction of TDS (total dissolved solids).
? It has a favorable 2 to 1 permeate (purified water) to brine (rejection water) rate.
? It requires no booster pump, therefore no electricity.
? It operates silently.
? A handy water pressure gauge is pre-designed into the unit on the cap.
? It is sturdily constructed. And since there are a lot fewer moving parts and tubing compared to systems using pumps, it should outlast many other under-the-sink options, and with less possibility of leakage.
? Reverse osmosis remains the gold standard in water filtration. As with all RO systems, including this one, they basically filter everything out of the water to 0.0001 microns (.1 nanometer). The pores are small enough to even filter bacteria and most viruses.

Note: There are only a few caveats:
1. Like all RO filtration systems, this system should be used often. If you don't plan on using it for a while, you'll want to follow the storage recommendations within the manual. I will be storing my filter cartridges in a plastic bag and placing them in the refrigerator when I'm away for more than a few days. Also, after weeks of non-use and storage, the membrane could begin losing its full filtration effectiveness.
2. Although, not technically considered acidic, RO water is stripped of all minerals which significantly reduces the alkalinity. The resulting low PH level is not what our bodies prefer. Our bodies thrive better on water that is more alkaline and spring-like in quality. Some people refer to RO water as ��dead water,�� since the PH is not alkaline and the taste is flat.
Well, the water is not really dead; it��s just not ideal. So, if purchasing this system I suggest adding an alkalizing and remineralization filter as a final stage before the faucet. They can be found on Amazon.
3. Since this system does not employ a booster pump, the pure water output (flow to the faucet) can be reduced during high water demand times with municipal water supplies. It should still be very adequate though.

this Purewell tankless RO system is impressive because it delivers 800 gallons per day without needing a pump or electricity which means zero noise under the sink and no power cable to deal with, the 2:1 pure-to-drain ratio is very efficient compared to older RO systems that waste way more water, the 7-stage NSF/ANSI 58 certified filtration removes PFAS, TDS and a wide range of contaminants, install was straightforward under the sink and the water tastes noticeably cleaner and better than before, the tankless design also means no stale stored water �� really well engineered RO system that punches above its price.

Ok, so.
I��ve used a few PureWell products at this point, so this isn��t my first experience with brand & won��t be the last.
My first purchase was one of their portable RO systems, which worked/Works great but what really stood out to me was their customer service. I was missing a part, reached out, and they not only sent the replacement quickly but also included an extra filter just as a courtesy. That kind of support goes a long way and a week or so later they message me to make sure I got it and made sure everything was working properly.

So when I came across this under-sink system, it felt like an easy decision to give a try.

One of the biggest advantages is that it doesn��t require electricity just water pressure so there��s no noise and fewer things that can go wrong. Installation was also easier than I expected.
It��s marketed as having tool-free quick-connect fittings, which is true, but you will need a few Tools like a drill and a wrench. Not a big deal, just something worth mentioning, watch the Video, and using Rufus to ask questions is getting much more helpful as Amazons AI assistant
(also a bit creepy) story for another time.

Now I��ll be honest most plumbing work I��m not a fan of, But when you own a home, you either learn to do it yourself or pay crazy amounts to someone for what ends up being a very simple Job that may take a professional 15 min vs a little extra time and learning yourself comes out absolutely the best way. After you��ve learned you can handle more than you thought and more, and adds to your Skill list. Seriously everyone now more than ever, is a time you should learn to do as much as possible! Makes more sense and definitely saves more money!
Even with removing my old system, the entire install took me about an hour.

Speaking of my old system, I previously used a Waterdrop unit. It worked fine, but after trying multiple PureWell products, I��ve been more impressed overall with their build quality and consistency.

The unit itself feels solid and well-made. The tank is a bit larger than I expected, but in my case that wasn��t an issue (Thankfully) I had recently upgraded my sink, so I had extra space to work with.

I��m on well water in a rural area, and filtration makes a noticeable difference. The taste is absolutely much better & I��m not a huge fan of plain water! I add electrolytes mix/packets, ANYTHING with flavor, but starting with clean, filtered water makes a difference.

Overall, this system does exactly what it claims. Between the performance, build quality, and especially the customer service, PureWell has easily made it into my top three brands.
I Just installed it last week so it��s barely broken in.

I��d definitely recommend giving this one a try!

I've been wanting to replace my very old R.O. under sink system and I picked up this Purewell U01 800GPD RO system because the specs are so impressive��especially the non-electric design, high flow rate, and compact tankless build. It seems like a huge upgrade to my current system which includes a bulky three-gallon water tank.

That said, I haven��t installed it yet, and that��s an important part of this review.

The reason I��m holding off is the current lack of available replacement filters. Obviously, filter availability isn��t just a minor detail��it��s essential to the long-term usability of the product. Even the best system becomes useless if you can��t maintain it. At the time of writing, replacements are not available, and although I did reach out to the company and was reassured that replacements will become available, until I can confirm that replacement filters are consistently available, I��m hesitant to install and commit to using it. An RO system is a long-term investment, and ongoing maintenance support is just as important as the initial performance. Also, the system itself is also listed as currently unavailable, which raises some concern, although as with the filters, I was reassured that it is not being discontinued and will be available again sometime.

From an initial inspection, the unit itself looks solid. It��s compact, lightweight, and the included components seem complete for installation. I love the minimalist design ��it looks clean and modern. The idea of a water-pressure-powered RO system is especially appealing��no electricity, no pump noise, and theoretically fewer failure points.

I also like the inclusion of the TDS display and pressure gauge, which should make monitoring performance much easier compared to more basic systems. The claimed 2:1 efficiency ratio is another big plus if it holds up in real-world use.

Bottom line: This looks like a promising, well-designed system with some standout features, and I'm hoping to be able to install it soon. I��ll update this review once I��m able to put it into actual use.

I looked at other systems that had complicated installations and were higher priced than the Purewell system. I was also familiar with the Purewell brand.
The filter is smaller than a lot of its competitors. The size makes it convenient, it takes up very little space under the kitchen sink, which never has enough room. Not needing an electric power is what really sets this filter apart from the others. There is no need for an electrician. This system can be setup on your own. It is quiet. I can't hear it at all. We use it solely for drinking water on top of our water softener. The water taste Great and is crystal clear. You can see and taste that Purewell put some work into the system. I wouldn't look at another brand at this point. We'll worth every penny.

There are many places today that have less than healthy water coming out of their tap and I live in one of those. Because I did not want to deal with water delivery or having to constantly go out to stores for water I thought I would try and find something that would be effective at making my tap water healthier for drinking. When I saw this I was curious and thought this might be just what I was looking for. I was absolutely right!
Made my tap water taste noticeably better. Took all of the weird chemical flavor out of it and now it just tastes clean. I also notice that my dishes that I hand wash do not have the calcium like deposits on them anymore when they dry in the air. That is amazing to me.
I anticipated this being a little difficult to install. I have very little in the way of DIY skills so if I can install this that is saying something. I did have a tiny bit of help but not much at all and was able to get this put in and working. I am so pleased with it and recommend this pure will tankless water purifier to anyone who needs something like this.

This RO system is seriously impressive. You can tell right away it��s been thoughtfully designed��from the layout to the included components. It comes as a very complete package, including the faucet, so you��re not scrambling to buy extra parts mid-install.

The tankless design keeps everything compact and clean under the sink, and the system runs ultra-quiet, which is a huge plus. The real-time TDS display and pressure gauge are great touches��they make it easy to see exactly what��s going on instead of just hoping everything is working correctly.

Water flow is strong for an RO system, and overall it just feels convenient and modern compared to older setups. If you��re looking for a high-quality, all-in-one filtration system that��s easy to live with day-to-day, this is a great choice.

I am a plumber by trade and I am very impressed with this system from top to bottom, but especially how easy they make it for everyday homeowners to install this system completely. Nothing is needed besides a small wrench and a drill to COMPLETELY install this thing. Nothing at all. No special p-trap piece to add or swap out for the waste water, no electric hookup or anything. They add a piece so you can use your already installed piping for the waste and everything else is pretty much a push fitting. And they make it even easier with the detailed directions and a video that shows every step. We got ours because the RO system we have now is not just outdated, but there are THREE filters are they are very expensive, kinda loud, takes up %70 of our under the sink counter space, and need changed every 90 days! That's a lose lose situation. Saw this, and jumped at the chance to try it and test it out. Nothing to lose in our situation. But found we had everything to gain. After a faster than usual install process for me, about 15 min, it was done. It took me about the same to take out the old one as well. The install process was not only fast, but it was easy too. The unit it self is larger than the pictures kinda lead on so make sure you pay attention to the height of it to insure you have the room where you are putting it. I have seen some under the sink spaces that do not have the clearance, especially in manufactured homes. So just make sure ESPECIALLY you have a double basin sink or a 'farmhouse' style sink and/or if the walls of the cabinet run really close to the sides of the sink basin(s). Just double check to avoid the slight headache of return processes. Back to the review: final ourxome is incredible water at a very impressive rate. We can fill out kids water bottle for school now in about 9 seconds where as before it would take 30-35 seconds. And the water taste is amazing. It has that one taste that RO water can only give you. If you know, you know! Very deserving, very raving, 5 star review! Not a single negative comment or even a concern or a suggestion. Just a great value for the money on all accounts!!!!

Working well making water

I love this system! It was easy to install, after reading through the instructions a couple of times (that’s my preference though) and the water is great now. No complaints at all with this and I love that it doesn’t require any electric hookups. Highly recommend!

this Purewell tankless RO system is impressive because it delivers 800 gallons per day without needing a pump or electricity which means zero noise under the sink and no power cable to deal with, the 2:1 pure-to-drain ratio is very efficient compared to older RO systems that waste way more water, the 7-stage NSF/ANSI 58 certified filtration removes PFAS, TDS and a wide range of contaminants, install was straightforward under the sink and the water tastes noticeably cleaner and better than before, the tankless design also means no stale stored water — really well engineered RO system that punches above its price.