Home » Water Softening » Water Softener Guides » Water Softener Regeneration Process: Frequency & Problems

Water Softener Regeneration Process: Frequency & Problems

Scott Winfield
Last Updated on
by Scott Winfield

If you live in an area where hard water is an issue and you have a water softener in your home, it’s likely that your unit is a traditional salt-based device. 

These devices come with tanks that serve to soften hard water as it passes through them. When the water comes out of the other end of the tank, the minerals that make the water hard (calcium and magnesium) are no longer present. So hard water comes into the tank, soft water goes out.

But how exactly are these minerals removed, where do they go, and how does a salt-based water softening system take care of itself?

This is where the water softener regeneration process comes into the picture. In this article, we’ll explain what it is, give you key pieces of info regarding how it should happen, and troubleshoot potential regeneration problems.

What is Water Softener Regeneration?

Water softener regeneration is the process of flushing out the calcium and magnesium hard water minerals that build up in the resin of a water softener so it can continue to function properly. Additionally, it serves to recharge the resin bed that’s responsible for removing minerals from water.

A water softener works through ion exchange, a process in which positively charged mineral molecules are attracted and trapped by a negatively charged resin bed (or beads) in the resin tank. This bed replaces the “hard” ions of magnesium and calcium with “softer” sodium ions.

However, the resin bed can’t maintain its negatively charged sodium status forever. Especially when it is already engaged in enough ionic exchange, this bed is likely to get saturated with all the calcium and magnesium molecules it traps.

So, to continue functioning properly, the system needs to clean and recharge the resin bed every once in a while. To that end, most traditional softening units feature two tanks: a resin tank where the softening happens; and a brine tank where a brine solution that flushes trapped minerals out and feeds the resin bed with fresh sodium is prepared.

Water Softener Regeneration Process
Water Softener Regeneration Process: Photo Credit – https://www.apswater.com/images/regen.jpg

Most devices come with a pre-programmed regen time that’s determined by the hardness of your water and the capacity of the device. When that regen time comes, the brine solution starts traveling through the whole system, sending trapped minerals down the drain and recharging the resin bed.

The Water Softener Regeneration Cycle

Here’s how the regen cycle works:

  1. The water softener cleans hard water
  2. The water softener’s resin beads get saturated
  3. The water softener switches frequencies and needs to be regenerated
  4. The water softener opens the brine tank and uses a salt block to prepare a brine solution
  5. The water softener flushes through the salt block, cleaning out the resin bed
  6. The water softener flushes through the entire tank, cleaning it and rinsing out excess salt
  7. The water softener switches back to its original settings
  8. The water softener cleans hard water

Each of these steps is done automatically except for salt block renewal. If you’re experiencing a downtick in water quality, it might be because your water softener is out of salt. 

In other words, all you need for an efficient regen process is the right amount of salt in the brine tank. You can find the best salt for your softener on the online store of the manufacturer of the device, but local appliance stores also have a variety of options on offer.

Unless you need to add salt to the device, the regeneration process happens automatically in a pre-programmed time, meaning you don’t have to do anything about it.

The frequency of salt replacement varies depending on the quality of the salt you use, and the water hardness that the device deals with, but the general rule of thumb for smooth operation is to do it once a month.

If you just started using a water softener, consulting with the manufacturer on when you should invest in more salt for your unit is also a good idea.

Water Softener Regeneration Frequency – How Often Should it Regenerate?

Water softeners regenerate once a week. Usually, they do this automatically and in the early hours of the morning or during the night.

Early morning or night is the best time for water softener regeneration because the regen process reduces the water flow to a trickle since the device is out of operation. That’s why most manufacturers pre-program their devices to regenerate when there’s low water demand in the house.

Although water softeners typically regenerate once a week, they can regenerate more or less often, as needed. This schedule depends on the type of water softener you have, as there are models with time-initiated or demand-initiated regeneration.

Time-initiated regeneration flushes the water softener after a certain time (usually once a week). It’s set by a small timer on the side of the softener and automatically resets once it’s regenerated.

Demand-initiated regeneration, however, measures the amount of water that goes through the softener. After a specific amount of water, it regenerates the tanks automatically and starts over.

You may also run manual regen cycles, especially when it’s time to clean your water softener. As long as you consult the instruction manual of the device and follow the guide step by step, it’s an easy procedure.

How Long Does Regeneration Take?

A water softener takes 30 minutes – 2 hours to complete regeneration, depending on the size, capacity, and manufacturer of the device.

Although the process itself sounds like it’s just basic flushing, it’s actually not that simple. The brine solution needs to have some contact time with the resin to dismantle trapped minerals and feed it an adequate amount of new sodium ions.

So, the size of the resin tank, which is directly correlated with how much surface the resin has and the contact time between the brine solution and the resin, affects the length of the regen.

Some innovative devices have an upflowing process, while most traditional ones have a downflowing one. During an upflowing regen, the solution enters the resin tank from below and moves upward, meaning that it lifts the resin up, unlike with downflowing regen, in which the resin is stable.

This lift in upflowing regen allows the solution to have more contact surface with the resin in less time compared to downflow. So, a device with an upflowing regen cycle might spend less time regenerating but turn out to be more efficient.

Almost every brand on the market provides information on the regen time of their devices, so it’s best to consult them before making a purchase since regen means that the flow rate is significantly reduced.

Water Softener Regeneration Settings

Most modern water softeners are set to regenerate automatically. When installed, they have a specific time to reset, which is mostly once a week.

However, you can change this setting if you need more water during regeneration. Just make sure you consult the instruction manual of the device or the customer service of the manufacturer if it’s your first time doing it.

What Does Water Softener Regeneration Sound Like?

Water Softeners emit a low, humming sound accompanied by flushing noises during regeneration. There’s also a chance you’ll hear some machinery whirring when the machine clicks the system from softening to regenerating. This is normal and shows that the device is doing its job.

Can You Use Water Softener While Regenerating?

It depends on manufacturer guidelines. Some water softeners come with dual resin tank setups or specific water reservoirs so that the regen process doesn’t affect water use, but that’s not the case for all models.

Most devices have one tank whose process might be adversely affected by the use of water during regen. Additionally, since the resin tank is full with a brine solution when it’s regenerating, the water you’ll get will probably be salty.

Lastly, the regen process mostly means you’ll get low water pressure since the device is engaged otherwise. So, the water pressure you’ll get may not be ideal if you want to use a washing machine or take a shower.

In short, it’s not ideal to use a softening device when it’s regenerating.

Water Softener Tanks
Water Softener Tanks

How Much Water is Discharged From a Water Softener During Regeneration?

A water softener discharges 20 to 50 gallons of water during regeneration, which is usually six times the amount of salt in the system.

The amount of water discharged comes from two distinct rinses: the rinse to distribute the salt and the rinse to clear the excess salt. Since the salt block is about the size of the resin chamber, you need three times that amount of liquid twice in a row.

This may seem like a lot of water, but note that this tank has been cleaning hard water and mineral buildup for a while. To make a salt solution that will effectively remove those minerals efficiently, the system needs a few gallons.

Common Regeneration Problems

Of course, no machine runs smoothly forever. Some of the most common problems with softening devices are rust, getting stuck in regen mode, and loud noises during regen.

Not all these problems warrant a call to a professional plumber or technician. So, let’s see why they occur and what you can do to deal with them or prevent them.

Water Softener Rusty After Regeneration

If your water is brown or tea-colored after regeneration, your unit might require a little extra cleaning to avoid rust. Iron is the most common element on earth, and although most water softeners remove iron, when there’s more iron than 2 to 5mg/L in your water supply, it might still leach into the end product.

What’s worse, exposing the device to more iron than it can handle will quickly render the device ineffective since the excess iron will build up on the resin tank. Eventually, the brine solution won’t be able to flush it all out and it’ll show up in the water coming out of your faucets.

To avoid this problem, use an in-depth resin cleaner, like the Iron out for water softener, on top of the regular regeneration cycle. This chemical formula will strip off the rust and leave your resin sparkling clean again. You can head to our guide on how to clean a water softener for more info.

That being said, if the water supply is especially rich in iron content, the best course of action is to complement the softening device with a whole house iron water filter.

Water Softener Stuck in Regeneration Mode

Although water softeners automatically switch in and out of regeneration mode, the timing mechanisms aren’t always perfect. Sometimes they get stuck or broken, and the softener keeps regenerating and never softens the water.

In such cases, the first thing you need to do is to bypass the softening device and unplug it. Then, you can call customer support and learn about the manufacturer’s recommended course of action.

They’re likely to send a technician, and the technician will probably advise you to replace the timer of the device. Depending on the manufacturer, technician, and problem, the expenses might range between $100 to $600 for this particular problem.

Water Softener Making a Loud Noise During Regeneration

Water softeners typically aren’t very loud while regenerating. However, some can create a loud banging or mechanical sound as the unit resets.

For the most part, this is normal. It could just be the system resetting or the valve switching. However, if it bothers you or happens continually, you might need to call a technician.


Water softening devices remove hard water minerals through a resin bed charged with sodium. To cleanse this bed of trapped minerals and recharge it, a brine solution travels through the system in a pre-programmed process called the regeneration cycle.

This cycle mostly happens once a week, typically when the water demand of your household is at its lowest, and depending on the device, it lasts 30 to 120 minutes. When it’s time to clean the device, you can run your own manual regen cycle by consulting the instruction manual.

Although the device will usually still have water available during regen, albeit at a low pressure, we don’t recommend using water within that period. If the device takes too long, gets stuck in the process, or makes particularly loud noises when regenerating, you should call a technician.

On the other hand, if the water is brown, it indicates that there’s rust buildup in the system. You can take care of the rust problem with resin sanitizers, and you can install an iron filter to prevent further occurrences.

Sign Up For Free 2024 Water Defense Guide!

Join our 1 Million+ strong water defense community and get updated on the latest product news & gear reviews. Plus, get a FREE 21-page "2024 Water Defense Guide" with exclusive content NOT on this site!

We HATE spam. Your e-mail will never sold or shared!

Scott Winfield
Scott Winfield
My name is Scott Winfield and researching and writing about water filters and other strategies to purify water has become my full time passion in recent years. I'm glad that you found our site and you can look forward to authoritative and well researched content here to help you get the best in water.
  1. My water softener, possibly a Sentry II 960, is not working. I took out most of the salt to check the water level which is about 6″. I went to Regen and the brine tank was empty in about 10 minutes of a 60 minute regen cycle. I am wondering if it uses so much water because the resin is gone or shrunk so that channels are forming through it.

  2. What causes the time to change for regeneration? Ours used to go through the process @ approximately 2:00AM.
    It changed to doing the process in the afternoon. We did not make the change & we are in Arizona so there is no change to DST.

    Thank you

    1. Hi Kathy, thanks for reading and good question. Different systems have different characteristics of how the regen cycle works. Yours might be demand-initiated so that you may notice a “typical” time, but then with different water usage patterns in your household the timing can change. It could also just be a timer that has some kind of variable. The best way to know is to consult your system’s instruction manual or contact the manufacturer.

Leave a Reply

Your email address will not be published. Required fields are marked *