Water Softeners How They Work

Water softening is the act of reducing the level of magnesium and calcium ion concentration from hard water. Although the World Health Organization has found no evidence of hard water being harmful to humans, many people may still find it undesirable, mainly because soaps and detergents don’t lather well with hard water making it difficult for cleaning purposes. The best and the most used method of reducing hardness from water is to use a ion-exchange resin device, more commonly known as a water softener.

Water softener systems work by replacing the magnesium and calcium ions causing the hardness with sodium ions. The way it works is that the water passes through a negativity charges bed of resins containing sodium ions, though it can also use potassium or hydrogen ions. As the negativity charged particles absorbs and binds the magnesium and calcium ions it releases the sodium ions, thus replacing the hardness minerals with sodium. How much sodium is required for this process depends on the amount of hardness minerals in the water, the harder the water the more sodium ions is released in to the water to reduce the hardness. Such resins are also available to reduce the levels of carbonate, bi-carbonate and sulfate ions from the water, but they release hydroxyl ions in the water instead.

water softener how they workAs these resins become filled with undesired ions from the water they slowly lose their effectiveness and needs to be recharged. This is usually done by passing a highly concentrated brain of usually sodium chloride (salt for water softener), or potassium chloride, or hydrochloric acid solution through them. This process replaces the hardness minerals from the resins with sodium or potassium.

It should be noted that too much sodium in the body can potentially cause side effects, so if you have hard water problems, it would be wise to have two taps in the house, with only one of them running through the water softener that you can use for cleaning purpose, while the other one with hard water that you can use for drinking, since the hard water has not be proven to have any adverse effect on the body for drinking. It’s once again mainly a problem for plumbing and house cleaning/washing. Other solutions include using a saltless water softener which can either use a completely different water softening system that does not include salt or it might simply be something like a kinetico water softener that instead of using salt you use potassium chloride to recharge the water softener resin.

3 Responses to “Water Softeners How They Work”

  • Steve:

    My water softener has 2 controls. one controls how many pounds it uses during each regeneration and the other is set for days between regeneration. How do I know how to set these. I have the regeneration set for 2 days, I could set it for 3 or 4, etc. Main question is how do I know how many pounds of salt it should use for each regeneration. Second question, would it be better to use more pounds of salt for each regeneration and what exactly does the number of pounds of salt have to do with?

    Thank you very much.

    Take care and GOD Bless!


  • Nat:

    These settings really depends on your model, you will have to consult your manual. Many water softeners have a daily regeneration setting (they do it at night usually) so it seems yours might be able to wait longer but this is probably dependent on how hard your water is.

    The number of pounds of salt also depends most likely as the #1 factor on how much you need for your water, either you can ask the seller of your water softener to come test it out (ideally this would be done before purchase) and that way you would have a better idea of how much you need depending on how (once again) hard your water is.

  • abdallah:

    it depends on the amount of water you need also hardness of water
    to know when you have to active your softener you need to measure hardness every like two days
    take 50ml of sample (water after softener) and add EiroChrome Black T (blue complex turns to red in the presence of metals)

Leave a Reply