iSpring CU-A4 0.01μm Ultra-Filtration Under Sink Water Filter System, Tankless 4-Stage High Capacity, Remove 99.99% Contaminants, Quick Filter Change with Brushed Nickel Faucet, White
About this item
- SUPERIOR PERFORMANCE: The advance 4-stage design, which includes both Ultrafiltration and KDF/GAC stages, removes up to 99% of PFAS, chlorine and chlorine treatment by-products, lead, arsenic, and much more, while retaining minerals. Noted: This system is NOT a Reverse Osmosis water filtration system and does NOT lower TDS.
- 4-Stage ULTRA FILTRATION SYSTEM: PP Sediment Filter ((5 microns) removes larger particles like rust, sand, dirt. ) Ultra Filtration Filter (contains hollow fiber membrane technology with a pore size of just 0.01 microns. ) KDF and GAC Filter (provides much better control of particularly problematic contaminants including chloramine, hydrogen sulfide, heavy metals, and other compounds). Fine Activated Carbon Filter (provides final polishing).
- SIMPLE AND FLEXIBLE: NO WASTE WATER and No storage water tank required. The CU-A4 provides highly effective water filtration for any number of clean water needs - at the sink, in the refrigerator, for coffee makers and more.
- FEATURES: Come with premium brushed nickel finish drinking water faucet. All filters, tubing and other water-contacting parts are manufactured to comply strictly with NSF/ANSI standards for safety and water quality.
- EASY-TO-INSTALL AND REPLACE FILTER: Push to connect fittings with color-coded tubing simplify the installation process. Filter replacement are designed for ease. No need to disconnect hoses or water lines. Just Twist On / Twist Off filter cartridges make changing filters a snap. Filter life: 6 -12 months, depending on your source water and usage.
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iSpring CU-A4 0.01μm Ultra-Filtration Under Sink Water Filter System, Tankless 4-Stage High Capacity, Remove 99.99% Contaminants, Quick Filter Change with Brushed Nickel Faucet, White
$231.99
- Availability: In Stock
- Model: CU-A4
- Manufacturer: iSpring
Write Review

2016-02-24
Install was a bit tricky, it took two hours, mostly figuring out how to do it, not the work itself. Once we figured it out, it took hands down 15 min! We were lucky and our cold water was already separated into two since I was putting the filter in the place where I had hot water faucet. Water tastes so much better than the tap - you can really taste the difference! (Totally worth the trouble of the install! :)Arrived promptly, packaged securely in the box, but as other people claimed the instructions are a bit unclear for a not so handy monkey as me when it comes to plumbing. I think it might be too technical and sometimes vague. Since I am still somewhat handy, I could deduct from the images in the instructions that somehow one tiny tube stopper part was missing from the package.Well, what is a gall to do? I contacted the companys sell department though their website (123filter), and did receive a prompt response the next day. The whole issue of missing little fitting got promptly resolved free of charge, and even got a USPS tracking provided! Now, if that is not exceptional customer service - I dont know what is!The product itself feels sturdy; nothing feels cheap about this system. I must say that I love the faucet included! Oh! It is beautiful! Some of these faucets for these type of undersink systems are sold by other companies for 80 bucks, and it looks nowhere near what this faucet looks like! This looks like Neiman Marcus compared to Macy/ Target!The price for this system is fair - I dont think anyone is fleecing you with this product on quantity or quality, and you are not fleecing anyone either. What is a great deal are the replacement filters for a year go for about 80-90 bucks, which I think is also really good compared to other systems. I hardly use my GE fridge water filter and basically pay around that much for that filter for a year. AND if you have some issue with installation (one-time time investment) - contact iSpring - they got your back! :)I picked this filter on the day I decided that my new condo needed a undersink filtration filter. I already knew quite a lot about filters so I was not a novice in that regard. I knew what a good filtration system should filter and cost. If you are looking for a system right now, please make sure you look at good quality filters based on what is actually being filtered (filter type), original cost, and then also take into account filter replacement cost. I bought this filter system based on these criteria.Choosing a right filtration system is quite a pain, especially for under the sink products. It can takes a good month of research, comparison of products, and then finally price hunting. In the process one learns enough about water germs and contaminates to start believing that nothing short of atomically decomposing the water will purify it enough! I went though this before with another system, and didnt want to obsess about percentages of stuff that gets filtered that I did not even know existed prior to the clean water quest I now realize choosing a water filtration system really is!Brita was one of my first water filtration system that I had attached to my faucet after I had DC water authorities test my DC water in my fancy Dupont Circe apartment. I learned that my cold water had enough chlorine in it as recommend for a pool. That was ten years ago. Since I came to DC from Sweden, I must confess that I was at the time absolutely ignorant of the fact that faucet water could be harmful. So I started with Brita carbon filters, which followed other over the sink and under the sink water filters. Since then, I have solid quality filters everywhere, and I dont live in DC anymore! If you think chlorine is no big deal - try drinking pool water for three years and see how your insides feel.SIDENOTE:There are quite a few parts in the package; I do think it would be helpful if the company included pictures of all parts that should be in the package and how they fit together because most of them I wouldnt even know what to call. A youtube video as for the osmosis product did help a bit, and I think if there would be one for this product as well, since not all clean-water enthusiast are osmosis converts, that would resolve the whole installation issue completely!
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Start Download
CU-A4 Manual
How to install
Replacement Filters & Parts
Filters:
What's the advantage of the under sink water filter compared to a Reverse Osmosis water system?
Great question! How many gallons of water will be treated during a filter's lifespan, before they need to be replaced? Also, is there a change indicator?The cartridge set has a capacity of 1100 gallons. However, please be aware that the actual gallon life will vary from customer to customer. As with all replaceable filter cartridges, they have limited space to hold the contaminants they remove from your water. This means that the higher concentration of junk you have in your source water, the faster the filters will run out space to keep filtering and vice versa. The filter lifespan is 6 to 9 months depending on water quality and usage. Has anyone tested the water that comes out of the filter with a TDS meter? I checked mine today and found that the TDS was the same as the tap water.This under sink water filtration system is not designed to remove TDS. Instead, it keeps healthy minerals in your water. If you are insterested in removing TDS, we recommend to consider a Reverse Osmosis water filter, like RCC7 & RO500. Are Total Dissolved Solids (TDS) bad for you?Total dissolved solids (TDS) is the term used to describe the inorganic salts and small amounts of organic matter present in solution in water. The principal constituents are usually calcium, magnesium, sodium, and potassium cations and carbonate, hydrogencarbonate, chloride, sulfate, and nitrate anions. The lower TDS means the purer water you have. However, it does NOT mean that the lower TDS the better quality the water has. Whether or not TDS are good or bad depends on what type and amount of materials in the water. Some of the minerals are healthy, while some are harmful. If you want to have a better understanding of your water quality, it is recommended to use a water test kit or get your water tested by a third-party company. For more details of how to get your water tested, you can read this article here. Can I connect existing water line(previously connect to refrigerator,tiny size) to this under sink water filter or I have use a adaptor?Yes. If you want to use this as a main filtered water supply, you will want to need an adapter depending on the diameter of the tubing. If you have any more questions, please contact us at (678)261-7611 or open a ticket here. Does this remove flouride?Unfortunately this unit does not remove fluoride. You will need reverse osmosis in order to remove fluoride. Follow on to teeing off to icemaker: can the no-pressure faucet be used as non-air gap? if not, can a non air gap faucet be shipped instead?This system is intended for use with a no-pressure faucet which cannot be used as a non-air gap faucet. In order to use this system with a non-air gap faucet, you would need to install a pressure regulator (APR40) leading to the system. Where can I find the replacement filter for CU-A4 and how often should I replace it?
The filter life is 6-12 months, depending on your source water quality and usage. You can find the replacement filter set here. I want to use an oil rubbed bronze faucet. Can I buy any one I want?Yes, you can use any oil rubbed bronze faucet as long as is is an air-gap with 1/4\" connections. For more details, please contact us at (678)261-7611 or open a ticket here. Does this under sink water filtration system filter FPAS (the forever chemical)?We would recommend a reverse osmosis system for better removal of FPAS. Will this under sink water filter remove pfos and pfas?Yes, CU-A4 has a Ultra Filtration unit that can filter both. I have a coconut sensitivity. Is there a filter I can get to replace the fourth filter on the stage 4?Unfortunately, we do not have a replacement for them. All of our carbon filters have a coconut shell. Does this water filter under sink remove viruses?No, this product won't remove viruses. To remove viruses and other micro-organisms we would recommend a UV sterilizer normally found on our Reverse Osmosis systems or our whole house UV sterilizer UVF55. I have a iSpring 7 stage R/O system that needs to be replaced due to leaks. Can I install this water filter for sink in its place?This CU-A4 is not a Reverse Osmosis water filter. It is also smaller than your 7 stage R/O system and is designed for under sink use. We want to make sure how your old water filtration system was mounted and connected. So it is recommended to contact us directly at (678)261-7611 (M-F 9-5 ET) or open a ticket here. Does the under sink water filter system include the brushed nickel faucet (as shown) ?Yes. This system does include a faucet but it is the chrome colored one shown. What size space is needed to install? Height and depth?Product Dimensions are 10.5 x 4.5 x 12.5 inches. I'd say around 16\" x 16\" undersink space is sufficient enough to install the CUA4. It's also best if you can mount it on the cabinet wall. Can I remove one or more of the 4 filters and still run the system?No, all of the filters have to be in place. Why does this under sink filter system need three tubes going into the faucet? It seems very counterintuitive!The faucet in this under the sink water filter system not only regulates the pressure but it also works as a one-way valve that prevents backflow. The main water first goes into the faucet where high water pressure is regulated before it comes back out to feed the system. Is ther documentation that this undersink water filter will remove all uranium from my well water?Only Reverse Osmosis systems are proven to remove Uranium from your tap water. If you have any questions, please contact us directly at (678)261-7611 (M-F 9-5 ET) or open a ticket here. How affective is it on arsenic?The 0.01 micron Ultra Filtration (UF) stage removes up to 99% of most problematic pollutants including arsenic. Can it be connected to existing faucet, what is the flow rate in GPM?No, this intended to be used on its own separate dispenser and can't be used with the existing kitchen faucet. The flow rate is about 0.5 to 0.9 gpm. What is the average pH of the water after filtration?This undersink water filter has very little impact in the pH of your water. |