What is Hard & Soft Water?
The hardness of water is determined by the amount of calcium and magnesium ions present. The more ions – the harder the water, and the “hardness” of water can range from “slight” to “very hard”.
Soft water does not contain the dissolved compounds that make hard water hard. These compounds are added to the water naturally when rain water filters through minerals in rocks causing particles of calcium carbonate and magnesium carbonate to be suspended in the water. Areas with high levels of limestone will typically have harder water.
Hard water can be softened using a process to replace the calcium and magnesium ions of hard water with sodium ions.
How does a water softener work?
A water softener is plumbed into a buildings water supply and works using a process called ion exchange. This is where limescale forming magnesium and calcium ions are exchanged for sodium ions.
A mineral tank makes up the main part of the softener and contains the ion-exchange resin. This resin is negatively charged and attracts the positively charged magnesium and calcium ions.
Water enters and leaves the tank through a valve which controls the softening process. Once the resin has become exhausted a brine solution (water and common salt) is flushed through the tank which reverses the process and allows the resin to soften the water again.
The control valve can operate on either a time basis or a meter controlled basis, which is more efficient and uses less salt.
The benefits of a water softener
Some people prefer the taste of hard water due to the essential minerals it contains and these minerals are beneficial to the human body but it also has qualities that make it less suitable for many personal and commercial uses.
The minerals in hard water react with soap to form a scum. This is the grime found around the water line when a bath is rinsed; the cloudy appearance on drinking glasses and the cause of the limescale forming deposits on taps, sinks, shower screens and windows. It also effects the efficiency (and lifespan) of appliances such as boilers and kettles. Soap and detergent does not lather as effectively in hard water therefore requiring more cleaning products. Clothes and towels will also feel hard and rough when washed.
Softened water on the other hand can save industry and households significant amounts of money over using hard water.