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HQUA

HQUA-TWS-121 120V 55W 12GPM 1“ MNPT Inlet/Outlet, Whole House Ultraviolet Water Purifier Filter, + 1 Extra UV Bulb, + 1 Extra Quartz Sleeve

  • Based on 76 reviews
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Availability: In Stock.
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Arrives Friday, Oct 23
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Size: 1" MNPT


Features

  • 12GPM 55W 21 inch long and 3.5 inch diameter. MNPT Inlet/Outlet: 3/4" Inch.
  • NEW DESIGN. Idea from BIg Blue. Smaller Size, Easier to Install and integrate into the pipe system.
  • No Secondary Pollution. No change in taste, odor, pH or conductivity nor the general chemistry of the water.
  • 9000 hours Life of UV bulb. Efficiency Purification: Reduce 99.99% microorganism.
  • Professional manual book are contained. Installation, maintenance, troubleshooting are easy to finish with that.

Description

Since HQUA was first established in 2016, more than 100,000 U.S. households have benefited from our products. Back to 2016, we find most of the UV water purifiers are unaffordable for the families. And if you live in a rural place or small town/city, it would be difficult to get clean water directly from the pipes/wells/raining water. Then, HQUA was established, we aim to provide people, affordable, reliable, responsible products, and services for the water issues. All our products focus on water issues, which mainly include indoor drinking water treatment issues, as well as outdoor pond water circulation, decoration, and swimming pool equipment. The ultraviolet (UV) treatment process is an extremely quick physical process. Ultraviolet light mutates and/or degrades DNA. When the DNA is damaged, the microorganism becomes unable to function because its “instructions” are garbled or missing. A microorganism that has no instructions cannot function and reproduce. It will be rendered harmless and eventually dies. In the UV purification process, water is purified as it runs through a stainless steel chamber (also called a “reactor”) that contains a special UV- producing lamp. As the water flows past the lamp, the microorganism in the water receive an effective dose of UV, preventing them from reproducing. HQUA UV Water Purifier is a water treatment device that needs to be assembled, but it’s easy to finish. Each part of it have its own function, we will introduce them hereby: Part Number: TWS-12C-02 The UV chamber is made by 304 stainless steel, which was widely used in food industry, medical, considered to be stable and durable. Length-21 inch, diameter-3.5 inch, inlet/outlet 1” DN25 OD 1.31 inch/ 33.4 mm , no requirement of the water flow direction. Quartz sleeve (Part Number: HQUA-TWS-12Q) not only provide an interspace for the UV lamp, but also ensure high transmittance (90%) for the UV light. UV lamp (Part Number: HQUA-TWS-12L, GPH436T5L/HO standard 4-pin) provide enough UV light to destroy the DNA of the microorganism. Electronic ballast (Part Number: HQUA-TWS-5595EB) connect the UV lamp and the power (120V/60Hz), work as a controller in the system with 3.2 ft. (100cm) power cord and 3ft. (90cm) lamp cord. Green light on means everything alright, off when there is no power out. NOTICE: Pre-treatment: Water quality is extremely important for the optimum performance of your UV system. The following levels are recommended : Hot Water Warning The water in the chamber of this equipment can be very hot (Approx. 140 °F) during an extended periods of no water flowing. It would not be a problem if the pipe system is long enough to disperse the heat. But if it happens,it is recommended to purchase a temperature control valve if this is an annoying problem for you. If you need a system for HQUA-OWS-121 or HQUA-TWS-121, please search “B0D2XQZMRQ” or “HQUA WS-DV03” on Amazon. Maintenance

Brand: HQUA


Special Feature: Heavy Duty


Product Dimensions: 21"L x 3.5"W x 3.5"H


Material: stainless_steel_304


Capacity: 12 gallons


Included Components: Adapter


Package Information: Bottle


Installation Type: Mounting


Purification Method: Ultraviolet


Power Source: Ac


Other Special Features of the Product: Heavy Duty


Container Type: Bottle


Installation Type: Mounting


Purification Method: Ultraviolet


Power Source: Ac


LowerTemperature Range: 32 °F


Maximum Flow Rate: 12 gpm


Upper Temperature Rating: 122 °F


Supported Water TDS Level Maximum (PPM): 1000


Item Dimensions L x W x H: 21"L x 3.5"W x 3.5"H


Capacity: 12 gallons


Material Type: stainless_steel_304


Brand Name: HQUA


Included Components: Adapter


Model Name: TWS-121


Model Number: TWS-121


Warranty Description: Different parts in the system has different warranty period. The stainless steel chamber has a 10-year warranty. The electronic ballast has 1-year warranty. The uv bulbs and quartz sleeve has 6-months warranty. The warranty periods begin from the day of fist installation/operation.


Manufacturer: HQUA


Number of Items: 1


Unit Count: 1 Count


Number of Packs: 1


Part Number: 1021201


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Friday, Oct 23

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.

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Top Amazon Reviews

    • Seems to do the job, worth the money
Size: 3/4" MNPT
Easy to install with basic plumbing materials. Seems to work as my water tested negative for bacteria post installation. Seems cheap to run. Be careful installing the light / sleeve, very easy to break.
Reviewed in the United States on March 19, 2026 by James
    • Works! Now a year later, time for yearly maintenance...with two howto hints
Size: 3/4" MNPT
Review Image by Amazon Customer
Yearly maintenance consists of changing the UV tube and cleaning the quartz tube. Remove the old UV tube and put aside. Next, following the instructions, shut off the water to the unit, drain that loop and remove the gasketing rings on each end. Remember that gloves must be worn when handling quartz glass as hand oil will eat at them. Remove the tube and clean it, as per the instructions. I have clean softened water so the outside of the tube was fine. What the instructions don't cover is that the UV bulb heat causes outgassing of the plastic guard on the tube...which puts a film on the INSIDE of the tube (like the film on the inside of your car windshield). How to clean it, the instructions don't say. HINT #1: Get a 24" claw mechanic's pickup tool like this: www.amazon.com/ALINNA-Flexible-Grabber-Bendable-Reaching/dp/B098F3VWDV/ and a piece of paper towel. Gather a dry piece of the towel up in a LOOSE wad with the pickup tool and gentle feed it down the quartz tube, turning it gentle to wipe the inside of the tube. Gently pull it out. Now reassemble the tube in the filter house and reseal it with the o-rings and collars. Put on the gloves if you haven't and feed the new tube in. Now HINT #2: You have to unplug the ballast and replug it after connecting the UV tube to the ballast 4 conductor connector. If you never unplug the ballast before connecting the new lamp, it won't come on. Hope this helps. My original review, a year ago...this still holds.=================================== I've been a professional mechanical contractor. The gear was was well made and straightforward to install. The one item damaged in shipment was replaced cheerfully and immediately; they even gave me two in place of the one busted one. That's service and customer attention! ... show more
Reviewed in the United States on August 30, 2023 by Amazon Customer
    • Jorin acknowledged HQUA-TWS-12 Ultraviolet Water Purifier Filter for whole house
Size: 3/4" MNPT
My plumber recommended this unit. Seems to be working just fine. It's a little small, and I've read recent articles that shorter bulbs might not be doing as good a job as longer ones? Anyway, 6 months now using it and not difficulties, and I ain't got sick yet -- so there's that! Jorin acknowledged.
Reviewed in the United States on April 28, 2026 by Jorin
    • Easy Install -Great Product
Size: 1" MNPT
Review Image by D
Review Image by D
Great product! Easy install. I used a pre-filter before the carbon tank and a post filter after the conditioner tank to ensure no particles get into the UV light. Love the holes in the bottom cap that shows the light is actually on. Doesn’t come with any reducers as I use 3/4” hoses and the housing is 1”. Ensure you have rubber washers inside the reducer to avoid leaking as I originally had a slow drip with the pvc version I made from the home store before I went online and ordered better ones. Lastly, no adverse impact to water pressure, in-fact I removed an older water softener before installing this new system and my water pressure increased significantly. ... show more
Reviewed in the United States on January 19, 2026 by D
    • Fantastic customer service.
Size: 3/4" MNPT
I seldom post ratings unless I am exceptionally impressed with a product. This item was easy to install, is obviously quality built and works perfectly for our well water. The most impressive part, and what inspired me to write this review, was the exceptional customer service. When I first installed the unit, the ballast light came on briefly, then went out. I installed the replacement bulb that came with it, and it works fine. I sent an email to the company with the order info, and the next day received a response that they had already shipped a replacement scheduled to arrive the following day. After having so many issues with unanswered customer service requests, these guys were a breath of fresh air. ... show more
Reviewed in the United States on July 25, 2025 by Dave Alei
    • The instructions recommend 5-6" of metal pipe coming out of the unit!
Size: 3/4" MNPT
First off, the unit works great. Had the water tested before and after, and the bacteria is gone. I have two issues with the unit. First, the in and out ports are not labeled. Are they reversible? I don't know. The instructions don't make it any clearer. One pictures shows the inlet nearest to the UV tube, the other shows it on the one further away. I resorted to looking at all the pictures here to figure it out. Which brings me to the second issue. Looking at all these pictures, most people are plumbing it directly with PEX, which was my plan. However in scouring the instructions to figure out the issue above, I found a note that the UV unit must be installed with 5" of metal pipe at the inlet and outlet, to prevent overheating and degrading the PEX, releasing chemicals into the water. I had to run out and get fittings and pipe in order to do that, and it really changed the whole layout, needing 10 extra inches of space. Both of these issues could be more clear in the instructions, and also in the product description. Clearly a lot of people are either missing the proper way to install it, or just don't care. ... show more
Reviewed in the United States on August 16, 2023 by Steve
    • Top Quality and Service
Size: 3/4" MNPT
The HQUA whole house UV water filter was easy to install and eliminated any question of microbial contamination for my well water. Although the packaging was very solid, I did need to request customer support for damage that appeared to have been caused in transit. With a single email, the damaged items were immediately dispatched and were in my hands within a matter of days. I would definitely recommend HQUA for their quality product and outstanding customer service. ... show more
Reviewed in the United States on November 13, 2025 by Rafael

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