Fleck 9100 SXT Dual-Tank Water Softener Review 2021

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After the Fleck 5600 SXT and the 7000 SXT, we are now going to take a look at the 9100 SXT as the last part of our Fleck water softener series.

What’s special about it is that it continuously provides soft water without interruption. How? It’s quite simple actually: The 9100 SXT features a dual tank system. As soon as the active resin tank has exhausted its softening capacity and goes into regen, the backup tank fills in and can immediately provide more soft water.

While one tank is in service, the other has time to recharge its resin bed making the system ideal for large homes and light commercial softening.

Sounds like the perfect fit? Let’s find out!

Fleck 9100 SXT

Fleck 9100 SXT

Flow Rate:9-22 gpm
Capacity:24,000-110,000 Grains
# of People:1-7+
Metered Regen:

Our Rating

Fleck 9100 SXT Water Softener – Key Features

The Fleck 9100 SXT valve itself is made in the USA and can handle even extremely hard water.

In addition, low levels of ferrous iron shouldn’t pose a problem.

Flow rate? Between 9 and 22 gallons per minute, depending on which system size you choose – there are 7!

The smallest setup has 24,000 grains capacity, the largest 110,000 – no reason to worry about calcium, magnesium and other hardness minerals even in very large homes anymore.

9100 SXT Pros

As you might already know, a salt-based water softener uses salt and water for backwashing in order to recharge its resin beads that are used for the ion exchange process.

How much salt and water is needed depends on the individual conditions and system, but expect that probably a few dozen gallons of water will go down the drain. In addition, an average-size water softener with about 30,000 grains capacity uses about 6 to 8 lbs of salt per regeneration cycle. Of course, larger models use more.

This is why it’s important that you opt for a metered device. Metered meaning that the system actually measures water usage and based on the hardness level calculates how much salt and water is necessary for recharge. As a result, resource consumption is reduced to a minimum – benefits the environment and your wallet. Fortunately, the Fleck 9100 SXT is metered.

All in all, the digital control valve is easy to use and allows you to make all settings according to your preferences.

More pros:

  • Regenerates using softened water to keep valve and resin injectors clean
  • Salt savings due to no softening capacity needed as reserve
  • Seller provides 5-10-year warranties + 100% no-risk guarantee for peace of mind

Fleck 9100 SXT

The Fleck 9100 SXT – learn more on qualitywatertreatment.com

Installation + Startup Instructions

If you are decent with tools the installation should go smoothly.

In our opinion, prior plumbing experience is not necessarily required to set up this water softener, although it would certainly help. If you’ve completed a couple of DIY projects before and you have enough time and dedication, you will be able to pull this off by yourself.

The good news is that the resin ships loaded in the mineral tank which makes things a lot easier.

And don’t forget to contact the seller for assistance. From our experience, phone and email support responds promptly.

Here is what you need to do:

If a water softener is not equipped with a bypass valve, we recommend you provide for one for ease of maintenance. Also, make sure to comply with local plumbing codes.

  1. Always turn off the water supply as your first step.
  2. Choose a location close to a drain. This will help with air breaks and backflow issues.
  3. Check that the resin tank stands securely.
  4. Place the main control valve onto the tank.
  5. Cut the distributor tube to connect it to the top of the valve.
  6. Connect the drain line flow control fitting to the drain. Teflon tape helps to prevent leakages.
  7. Check that the brine tank stands securely.
  8. Put the system into bypass and fill the salt tank with water to about 1″ above the grid plate or to the top of the air check.
  9. Open the main water supply and check for leaks.
  10. Open any cold water outlet nearby and flush all installation debris.
  11. Close the outlet.
  12. Switch from bypass to service mode and let the mineral tank fill with water.
  13. When filled, open the cold water outlet one more time to release all air from inside the softener.
  14. Connect the valve to a power outlet.

As for the initial system startup, follow these steps:

  1. Make sure your softener is in bypass mode.
  2. Fill the brine tank with salt (as per your manufacturer’s instructions).
  3. Slowly open the bypass valve to remove all remaining air.
  4. Start a full backwash cycle and check for leaks.

Installation Video

Below is the only video we could find that demonstrates how to install the Fleck 9100 SXT. Watching videos for other valve models might also be a good idea. For most water softeners, the installation process is pretty similar:

The Package (Parts)

  • 2x resin tank (black)
  • Brine tank (black), 18″ x 33″ with safety float to prevent overfilling
  • Fleck bypass valve
  • 8% high capacity resin, WQA Gold Seal & NSF-approved
  • Support gravel
  • Bypass valve

Programming, Settings & Maintenance

Programming the 9100 SXT is a breeze. Only 4 steps are required:

  • Set how often you want the system to regenerate (measured in days).
  • Set the regeneration time.
  • Specify your water hardness in grains per gallon.
  • Set the reserve capacity. This defines how many gallons per day you want as a reserve, so you still have softened water in the evening.

Abundant Flow Water Systems did a great job at explaining the basic programming of all Fleck SXT valves in their video below. The video features the 2510 SXT, but in fact it works the same for all SXT models:

9100 SXT Cons

So far, we don’t have any complaints.

Fleck 9100 SXT Review: Our Verdict

As a dual tank system, the Fleck 9100 SXT provides a never-ending supply of softened water around the clock.

Users have praised it as a great working unit that can compete with the big names in the industry. The low price is the icing on the cake. Double thumbs up!

More Reviews:

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This completes our Fleck 9100 SXT review. If you have any questions, please don’t hesitate to leave a comment below!

About the Author Tim Stanley

Tim Stanley is our content creator veteran. His daily tasks involve everything from research to editing. His expertise: Water Softeners. When he is not working, Tim spends most his free time cycling and shaping his body doing calisthenics. To calm down he also likes to watch Netflix (who doesn’t?).
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