iSpring RCB3P Tankless Reverse Osmosis Filtration System, 300 GPD Under Sink RO System, Reduces TDS, 1.5:1 Pure to Drain, Booster Pump & Pressure Gauge for Residential & Light Commercial Use
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Availability:
In Stock.
Arrives
Sunday, Aug 2
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Size: 300 GPD RO Tankless
Features
- Under Sink RO Water Filtration System - This high-capacity reverse osmosis system removes up to 99% of over 1, 000 contaminants and hardness, including PFAS (PFOA and PFOS), lead, chlorine, fluoride, arsenic, asbestos, calcium, sodium and more
- Durable RO System & Easy Installation - Freestanding stainless steel frame and metal hanging bracket. Makes your installation and filter changes easier while adding a protective buffer for your system.
- High Production Rate RO Water Filter - Super-efficient RO membranes deliver up to 300 gallons of purified reverse osmosis water per day, removing a wide range of contaminants as small as 0.0001 microns.
- 1.5:1 Pure to Drain Under Sink Tankless RO System - The built-in booster pump increases purified water production by raising water pressure. Compatible with 11- or 20-gallon iSpring storage tanks. TANK NOT INCLUDED
- Residential & Light Commercial Use - The iSpring RCB3P tankless reverse osmosis system is perfect for light commercial use, delivering high-quality RO water to restaurants, salons, labs, and officeseach benefiting in their own unique way.
Brand: iSpring
Special Feature: Reduce TDS, Tankless, Water Saver Technology
Product Dimensions: 19.5"L x 11"W x 28"H
Material: Stainless Steel
Capacity: 300 Gallons
Included Components: Filters, parts and tubing
Package Information: Tank
Installation Type: Freestanding
Purification Method: Reverse Osmosis
Power Source: Ac
Other Special Features of the Product: Reduce TDS, Tankless, Water Saver Technology
Container Type: Tank
Installation Type: Freestanding
Purification Method: Reverse Osmosis
Power Source: Ac
LowerTemperature Range: 40 Degrees Fahrenheit
Maximum Flow Rate: 0.2 Gallons Per Minute
Operating Pressure Range: 25-90 PSI
Upper Temperature Rating: 100 Degrees Fahrenheit
Supported Water TDS Level Maximum (PPM): 2000
Smart Home Compatibility: Not Smart Home Compatible
Item Dimensions L x W x H: 19.5"L x 11"W x 28"H
Capacity: 300 Gallons
Item Weight: 52 Pounds
Material Type: Stainless Steel
Brand Name: iSpring
Included Components: Filters, parts and tubing
Model Name: RCB3P
Model Number: RCB3P
Warranty Description: 1 year limited warranty
UPC: 662425023554 662425048076
Global Trade Identification Number: 54
Manufacturer: iSpring Water Systems,LLC
Part Number: RCB3P
Item Type Name: iSpring RCB3P 300 GPD Light Commercial Reverse Osmosis RO Water Filter System with Booster Pump
Unit Count: 1.0 Count
Frequently asked questions
If you place your order now, the estimated arrival date for this product is:
Sunday, Aug 2
Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
To initiate a return, please visit our Returns Center.
View our full returns policy here.
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Similar Products
Top Amazon Reviews
Size: 300 GPD RO Tankless
We purchased the iSpring RCB3P Reverse Osmosis RO Water Filtration System, 300 GPD system in 2017. Initially there were damaged parts from shipping but the parts were promptly replaced (Nick from customer service is awesome). Our water was high in sodium and this system reduced the TDS from 450 to under 30. Prior to this system I was buying filtered water in 3 and 5 gallon bottles which was running me over $300 a year so this system has paid for itself multiple times. The system has worked flawlessly since 2017. We couldn't be happier with this unit. The frame of the unit is quite hefty and the motor, pressure gauge, and other electronic items appear to be installed well. I will update my review after I am able to test the unit. This unit cost over $500.00 so the initial issues are very disappointing especially since I have no idea how long it will take to get the broken part. 1/16/18 Update I sent iSpring an email via their Contact Us option from their website late at night after posting the above review.. I received an email from one of their representatives (James) the following day. He has been working with me to resolve the broken Inline Carbon Filter connections. He first had to verify my purchase. He is in the process of shipping me the replacement part now. So at this point iSpring customer service has been very responsive implying that they are concerned about the quality of their products and customer satisfaction. I will provide more feedback once I am able to test the unit. 1/21/18 I received the replacement Inline Carbon Filter on Friday 1/19/18. I was disappointed in that the replacement filter was a 1500 gal rated filter and the original filter was a 3000 gal rated filter. I'm upgrading this to 4 stars, if I hadn't had to deal with the connector issues and if I had known that I needed to do all the reducing and expanding of tube connections I would have given this a 5 star. The following information may help prevent some frustration. I believe that ISpring has some quality control issues since the iSpring RCB3P GPD Commercial Grade Reverse Osmosis Water Filter System w/Booster Pump and Oversized Pre RO Filters unit was damaged upon arrival and the iSpring 20 gal storage tank I purchased was also damaged upon arrival. The damage did not alter the functionality of the units they just caused some frustrations. During the test phase of the RO system I found another connector that had been broken during shipping. I didn't find the second broken connector until about 8:30 PM when I opened the water valve to the RO unit. Very inconvienent running to a parts store when they are all closing. I'm not sure why but the design of this RO unit (RCB3P) has an input of 3/8" OD tubing but the tube size is reduced to 1/4" OD tubing through the membrane cartridges and carbon filter. The output lines to the faucet and storage tank is 1/4" OD. The input to the iSpring 20 gal storage tank is 3/8" OD. I wasn't able to find connectors that reduce from 3/8" OD to 1/4" OD and visa versa so I had to spend a lot of time at hardware stores to find parts to do the trick. This is very frustrating and inconvenient for the customer. I will say that once all the issues were fixed the unit appears to be working well. My TDS reading before the unit was 435 and the TDS reading from the RO faucet is 26. I did run the unit for some time before taking the RO TDS reading since I wanted to flush out all the lines. In addition, the storage tank recommends that the tank be flushed after the first filling. Be sure to run the faucet and tank lines into a bucket or drain before connecting them to the house RO line and tank, this flushes out the lines all the carbon from the carbon filter. On the positive side: I installed a sharkbite pressure guage and a sharkbite shutoff valve just before the reduction from my house 1/2" copper line to the 3/8" OD tubing line. My pressure is slightly over 50 psi going into the unit. Our water pressure from an outside faucet typically fills at 5-6 gal per minute. The RO unit produced about a gal of RO water a minute with about a gal of waste water (to get this information I placed the drain hose in a 5 gal bucket and the RO faucet hose in another 5 gal bucket and timed the test). I'm not sure how this unit works without the booster pump but I highly recommend getting the unit with the pump since all the wiring and other electronics are already installed. Don't be alarmed if the pump appears to run for a long time. Once I started filling the tank It took about two hours for the tank to fill and the unit to pressurize enough to turn off the pump (the gauge on the RO unit read about 1 when the unit turned off). When the unit turns off the water coming out of the waste water line will also stop. Our RO water has no smell or taste so I'm not sure why some of the other reviews had those complaints, maybe they didn't flush the lines and tank and some of the flux or other plumbing chemicals got into their tank and now it's hard to get it out. As I did, I suggest placing both RO output water lines (line to the faucet and line to the tank) into a bucket or drain before connecting the lines to the faucet and tank, this will help remove anything in the lines and avoid contaminating your tank. I ran my unit in this configuration for about 20-30 minutes. It's been one day and now that the unit is working my frustration is quickly diminishing. I'll keep my fingers crossed that the design of the unit is a good design. Good Luck.
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Reviewed in the United States on January 12, 2018 Reviewed in the United States on January 12, 2018 by lily
Size: 300 GPD RO Tankless
I’m extremely satisfied with the reverse osmosis water filtration system from iSpring Water Systems. I’ve been using it for 8 years now, and it has consistently delivered outstanding performance. The product quality is excellent — it truly made a noticeable difference in the final result of my product, especially since water is one of our key ingredients. The purity and consistency have significantly improved, helping us elevate the standard of what we deliver to our customers. Another highlight is their customer service: fast, efficient, and very helpful. On top of that, filter replacements are simple and hassle-free, making day-to-day maintenance easy. Highly recommend!
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Reviewed in the United States on April 16, 2026 Reviewed in the United States on April 16, 2026 by PEDRO
Size: 300 GPD RO Tankless
We used this for a while home RO system, running 2 fridge/freezers with ice maker, 2 RO faucets and a dedicated ice maker with no issues. The first one we installed had an issue, but Nick over at iSpring took care of it. It was so easy to get support and install, I can't say enough good things.
Reviewed in the United States on May 5, 2026 by WRoberts
Size: 300 GPD RO Tankless
I bought the RCB 3P 300 GPD system in Oct 2020. The system has 3 RO membranes ,MC-1, each rated at 100 gpd RO output. The unit feeds a 200 gallon storage tank and separate pump for whole house use. We use between 100-250 gpd- the average is 150 gpd. The RO water comes out at 10 PPM . I added a calcite tank to improve the taste . Capture ratio C= 52% . Actual measured RO flow is 320gpd. After 4 months we have used a total of 18,000 RO gallons. I believe the iSpring MC-1 membranes should last to 24,000 gallons. This is a real whole house system and very reasonably priced. Be sure to change your 3 prefilters at 24,000 gallons into the system. This will prevent any chlorine from damaging the RO membranes. Don at iSpring customer support - [email protected] - helped me to increase capacity and flow. I added a 4th RO membrane which Increased output to from 320gpd to 430gpd (see photo). The pump runs fine at 122psi . I used the existing 450 restrictor. RO pure at 15 ppm. Capture ration is 55%. This iSpring unit is amazing! I call it the “Little Engine that Could!" Next I will try to increase capacity by using the 150 gpd membranes. Don at ISpring support has given me excellent support! Update July 27, 2022: My ISpring RCB3P 300 gpd system has performed well for the last 13 months. With FS-TFC 100gpd membranes (3) I use about 150 gpd RO with 12 PPM and C= 60% The membrane life was about 15,000 gallons! Recently, I installed 3 X 150 gpd RO by Membrane Solutions and I am getting C=75% at 10-12 PPM. This is a great unit and very cost effective. Customer service from Don has continued to be outstanding!
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Reviewed in the United States on March 1, 2021 Reviewed in the United States on March 1, 2021 by Shepherd22
Size: 300 GPD RO Tankless
I purchased the iSpring RCB3P Reverse Osmosis RO Water Filtration System, 300 GPD system in April 2022. I have had this system for over 3 years. This is a great RO system, very well made and meets all my expectations. I put a tank with my system so that there is immediate good water pressure ready on the RO supply side. However, with the pump on the system one does not need a tank, I just preferred one. I recently experienced a leak in the housing of the pre-filter so I called ISpring. I talked to Nick who was very helpful. Nick explained that my leak could be due to high pressure on the supply side and possible pressure surges over the several years of service. Even though my system was out of warranty, Nick is gracisouly sending me a replacement housing and a pressure regulator to install on the water inlet side to regulate the pressure (max of 70 PSI). I am very grateful to ISpring for helping me solve my problem by sending me what I need (free of charge) even though my system was out of warranty. Thank you Nick, your quick service and kind response to my problem is greatly appreciated!! PS.. About 2 months ago I purchased a 2nd iSpring RCB3P system for a 2nd house. I highly recommend this system and ISpring. Their support staff is the best!
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Reviewed in the United States on August 21, 2025 by Robert Matousek
Size: 300 GPD RO Tankless
I purchased my iSpring RCB3P RO filter system to put on the front end of my mist cooling system to reduce the negative impacts of the hard water on the mist cooling pump, the nozzles, and all the furniture, glass, tile, and stone in the area under and around the mist nozzles. I hadn't noticed that at time of purchase there was a note the said "Condition: Used - Like New - Item will come in original packaging” albeit there was about a hundred and some dollar price difference compared to the the typical price posted on the Amazon website. When I received the RO unit the box was in decent shape, no outward signs of rough handling. However when I unpacked the box I started to get worried as the RO membrane housings were all shaken loose and dangling from their hoses. The top carbon filter was hanging from one hose and the tee on the other end was snapped clean off. The RO membranes and the pre-filter cartridges were brand new and still in their sealed wrappings. But suffice it to say I could not run the system in that condition. I contacted iSpring customer support through the link given on the Amazon web site. The next day I received a call from Nick at iSpring. He pointed pointed out the condition note but without hesitation he set up a warranty claim and shipped me a full replacement unit less the pre-filter cartridges and membranes as the ones I had were unused. After receiving the replacement unit I found the setup to be very straight forward. The manual explains the steps very well. For my system I have a total of 8 gallons of accumulator tank capacity which takes a very short time to fill and seems to be plenty for the demand of my mist system. Over the past week I have been testing and running the unit and can say the reduction in the TDS is considerable and measurable using the ratio method. After many hours of running the cooling system I have no visible fine white film on the glass and stone that I would normally have as the water residue evaporates. I am very satisfied with my purchase and the customer support I received from Nick at iSpring.
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Reviewed in the United States on March 27, 2022 by david prior
Size: 300 GPD RO Tankless
Unlike every other filter housing assembly I have seen, the housing is female and the cap are male. By itself this is not problem but there is no groove for the O-ring, and no matter how many times its carefully removed and re-positioned it simply falls within the threads which means it wont sit flush in the joint between the housing and cap. While you should not have to use teflon tape and NSF potable water safe thread sealants where an O-Ring is involved, I have tried both this thing leaks like a geyser. It will....not....seal! I'm a construction professional that purchased this for the renovation of my own house and left it in the box for quite some time before installing, so I'm beyond the warranty period. That said defective parts should not be a point of debate. I have installed other iSpring systems that have worked great. Lets see what the iSpring folks do about these defective parts....iSpring?
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Reviewed in the United States on July 7, 2020 by sfg
Size: 300 GPD RO Tankless
This RO has been a workhorse and has performed flawlessly for over 3 years until it stopped working. My well water is rough and raw. I have a chlorine/alum filtration system but the water is still undrinkable. The water before the I-Spring RO is 450-500PPM. After RO filtration is 6-12PPM and tastes as good or better than any bottled water out there. I called customer service and a person actually answered the phone. Michele, who was also helping me with technical support was great. After explaining the problem to her she stated that she would be sending me out a new unit!!! So I placed the call on a Monday and had a new unit at my door on Wednesday, 2 days later. The unit was out of warranty as well. This type of service from any company is unheard of these days. Michele was kind, courteous and efficient in making sure I would have a system replaced in record time. I-Spring has an excellent product and is tremendous in it's customer service. They have gained a life long customer.
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Reviewed in the United States on October 10, 2024 by Happy*