Water softeners play a vital role in softening the water for millions of people worldwide, but there is often a lot of confusion about how they work. By understanding exactly how these systems operate you can make an informed decision about not only if a water softener is suitable for you, but which type meets your specific requirements. Let’s get started by exploring what defines a water softener before we look into how they operate.

What Is A Water Softener?

Put simply a water softener is an appliance designed for the sole purpose of softening your water. They are usually placed at the point where water enters a property, just after the stopcock, to allow the feeding of appliances or processes with softened water. Feeding your property with softened water brings several notable benefits including reduced energy bills, improved boiler efficiency and even relief from eczema. To be classed as a ‘water softener’ the system must remove the hardness molecules from your water. Some solutions which prevent limescale formation without actually altering the chemistry of the water are known as ‘water conditioners’ instead.

Want to learn more about water conditioners? Read our comparison for more information

How Does A Water Softener Work?

The most important stage in the water softening process is something called ion exchange. All water softeners on the market utilise this process to remove the hardness from your water.

By definition, the ion exchange process is where limescale-forming molecules such as Calcium Carbonate (CaCO3) and Magnesium (Mg) are removed from your water and ‘exchanged’ for molecules of Sodium Chloride, better known as salt for the majority. Inside a water softener there are thousands of tiny negatively charged resin beads. As hard water passes through, these resin beads attract positively charged minerals and remove them from the water, exchanging them for sodium ions. A simplified view of this process is shown in the diagram below.

Why Do Water Softeners Regenerate?

The next step in the water softening process is something called regeneration. In simple terms, this is the cleaning process employed by water softeners to enable them to continue softening your water.

All the while that water flows through your water softener, the charged resin beads pick up hardness molecules and exchange them for Sodium ions, which generates soft water in the process. As there is only a set amount of these resin beads in your softeners ‘resin bed’ it is easy to understand that the amount of hardness molecules they can take on is finite. Once the capacity has been reached, a regeneration needs to occur.

There Are 3 Stages Involved In Your Water Softener Regenerating: 

1. Draw Of Water From The Brine Tank – TThis is where water heavily concentrated with salt is drawn from the ‘brine tank’ and flushed through the resin beads. This bombardment of sodium ions helps to dislodge the hardness ions from the resin beads in a process known as ‘reverse ion exchange’ which usually takes up to half an hour.
   
   
2. Resin Bed Rinse – Using the softeners normal feed water the resin bed is slowly rinsed in order to churn up all of the beads, dislodge any final hardness molecules and remove any excess brine that was used to re-charge the resin beads. This tends to take around 30-45 minutes to complete.
   
   
3. Brine Tank Re-Fill – The final stage of the regeneration process is the re-filling of the brine tank. This is where the brine tank refills with fresh water ready for the next regeneration.

This regeneration process means resin beads can be used for up to 20-25 years before they need replacing

How Do Water Softener Valves Work?

To control regeneration cycles all water softeners employ a type of valve. These valves usually come in two different forms, either metered or time based. Metered valves work by monitoring the volume of water used between regenerations, where as time based valves work by regenerating at a set time no matter the volume of water that has passed through.

In most cases water softener valves require you to enter your water hardness figure, this helps to ensure the system can perform as efficiently as possible – reducing the potential for waste water and preventing unnecessary regenerations.

Electric Verus Non Electric Valves
It is worth noting that there are two different ways a water softener valve can be powered, with electricity or using the kinetic energy from the flow of water (also known as non electric). Although there are variations in valve types, the ion exchange principle remains exactly the same.

Want To Learn More About Water Softeners?

Now that you’ve delved into the intricacies of water softeners and gained a comprehensive understanding of their operation, why not elevate your knowledge to new heights? Explore our ultimate guide to water softeners where you’ll discover an extensive wealth of information, equipping you with everything you need to navigate the realm of soft water with confidence.