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

2016-09-23
I am a General Contractor/Home builder. We originally had a RO system that provided us with excellent tasting water, but took up most of the under-cabinet and had to be sanitized with bleach at each filter change.. We dont have hard water and our tap water is drinkable but we wanted it cleaner, and the RO had intermittent leak problems. Could I find a system that would relieve us of the clutter , the maintenance, the water leaks under the cabinet, and still get great water?I decided to give the CU-A4 a shot. SO, Here goes what I didnt like, and then what I liked:CONS:1. The directions do NOT adequately describe how to make the water connections. To someone who has installed with these type connections it is an obvious "no-brainer", but to the rest of us.........Parts of the directions appeared to be for a different unit, and especially the section on installing the faucet, which was obviously from their RO system and was not anywhere close to describing the faucet enclosed. The faucet enclosed is an "air gap" style which requires a hole in your sink deck or in your counter of 1 1/8" minimum. The threaded pipe that will go through this opening is 1" in diameter. If your existing hole is anywhere from 1 1/2" to 1 1/8" the provided washer will work fine.2. While there was plenty of 1/4" tubing to do the installation, There are 3 colors of tube, red, white and blue. They provided plenty of blue and white, but not red, therefore I used white and labeled it red to make the job a clean install.3. There is no discussion in the manual of run-in time after completing the install. The water was barely drinkable after letting it free-flow for approximately 10 minutes as suggested in the notes . After flushing the system with approximately 15 more gallons the water was crystal clear and the flavor has become progressively better and better and has stabilized.PROS:1. The system IS actually easy to install when you have familiarized yourself with everything they have sent and how it will work with your existing plumbing and sink. AND you have purchased anything you might need so the system will integrate seamlessly.2. The snap-fit connections work great and do not leak a drop.3. Twist on replacement filters. How could it get any simpler???4. Takes up minimal space.5. The faucet is all metal construction.6. After initial flushing and after the first week of use (approx. 1 Gal per day)t the water tastes GREAT.As good or better than any of the bottled waters we have tested against.7. Every time I have called them (of course during business hours...duh...) they have been very responsive.So, customer service gets a nod.CONCLUSION:Well worth the money,Simple design and installGreat tasting waterNOTES:1.There is a review about salt taste. If you have softened water, then you may want to contact yourservice company regarding what is best to work with your existing system. At the very least do an internet searchon how softeners and filters can work together before purchasing this system.2. There are reviews that mention a 1/2" 3-way valve and having to buy adapter fittings. My system came with a 3/8 to 3/8" 3-way valve (which worked perfectly), so it seems iSpring has changed it to the more typical size.3. One reviewer gave 3 stars because this system does not reduce TDS and it cost them 10% restocking to return it.TDS is reduced by RO systems, This is NOT a RO system. iSpring does not claim reduced TDS. If you need reduced TDS...iSpring has a very highly rated RO system ( http://www.amazon.com/iSpring-RCC7-Reverse-featuring-See-through/dp/B003XELTTG/ref=cm_cr_pr_product_sims?ie=UTF8 ) for about $200.00.4. Most every review says the directions suck. I can attest to that. They do!Layout everything from the box, familiarize yourself with it, identify any problems with your existing plumbing. Take the 3-way valve with you to your local home improvement store and buy whatever you need.5. Make certain you have the correct tools to accomplish the install.6. For a water tight connection fit, remove the blue "horseshoe" clips and FIRMLY push the 1/4" tubing approximately 5/16" in to thecouplers until you feel it "bottom out", check the assembly by firmly pulling on the 1/4" tubing. Replace the blue clip.7. I made all of my tubing the same length and long enough for me to remove the filter manifold a couple feet from the cabinet to facilitate changing the filters when that time comes. The tubing is coiled and taped up (love that blue tape), and will be easy to undo and stretch out.8. I purchased an extra set of filters ahead of time, and store them right next to the unit.9. Instead of changing my filters by use of a calendar (such as recommended by the manufacturer, every 6 months), I will change them based on usage. Since we only use it for drinking and cooking, we likely will never hit a max avg of 3gals per day. Most filter manufacturers claim 6mos. is relatively equal to 1200 Gals. Therefore 3 gals x 365 days = 1095 gals. (1095 is approx 90% of 1200 filter life). That is when I will change mine, at about 1 year. You also can adjust your schedule based on this formula. If you use 6 1/2 gals per day, you will hit the 1200 threshold at about 6 months. Were you to use 10 gals per day you would want to replace the filters after 4 months. AND so on.If you dont have a basin wrench, get one from your tool store, (see images) Make your life easier.
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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. |