The resin is one of the essential media used in an ion exchange water softener. Most people don’t know that there are different types of water softener resin and which resin is best for their system. In this article, we will discuss the various types of water softener resin.
What are water-softener resin beads?
Water softener resin beads are a type of media used in salt-based water softeners such as twin tank water softeners, traditional water softeners, and cabinet-style water softeners to soften hard water.
They are also called ion exchange resin or zeolite beads.
The process of water softening by using these beads is called ion exchange. The water-hardness minerals like calcium and magnesium are positively charged. When water-softener resin beads come in contact with hard water the water hardness mineral stick to the resin beads which are negatively charged. The process makes the water softer and less likely to cause scale buildup in pipes.
What is water softener resin made of?
Water softener resin is made of string/thread/strand of Polystyrene which is wrapped in crisscross foam along with Divinylbenzene (DVB). Divinylbenzene (DVB) acts as a glue to hold the resin together. The crisscross or connection of polystyrene in water softener resin is called a cross-link.
The number of crisscrosses determines the strength of the resin and how long it will last. Continue reading below to understand more.
What are the different types of water softener resin?
Water softener resin types include
- Standard cation resin
- Fine mesh resin
Standard cation
The standard cation resins are best if you have water with less than 3-5 ppm of dissolved iron. It is meant to last 10–15 years but depends on the quality of the water.
The standard resin has a connection between the resin beads which varies from 2-20%. The connection between the beads in a water softener is called cross-linking.
Since cross-linking varies between 2-20%, the most commonly used percentage in the water softener is 8% and 10% percent cross-link.
For easier understanding, it is like making a ball using string.
10% crosslink resin has more strings interconnected, making the resin strong and lasting longer. It is best for chlorinated water without iron, so it is best for municipal water. Also, this type is more costly than an 8% cross-link.
8% crosslink has less string and is most commonly used in water without chlorine, making it best for well water.
Fine mesh resin
Fine mesh resin has small-sized beads. It can remove dissolved iron up to 10ppm and is best for homes with a private well.
The fine mesh is a bit expensive and gets fouled easily compared with standard cation resin. Since it gets fouled easily, it will require more frequent backwashing compared to standard resin.
Also, since the fine mesh resins are small in size, you require an upper flow basket to help prevent the beads from coming out during regeneration.
Knowing what types of water softener resins are available on the market now allows you to determine what kind of resin is currently in use in your system.
How can I tell if I have standard cation resin or fine mesh resin?
It is hard to look with your naked eye and tell whether this is fine mesh or standard resin.
A simple test can help differentiate. Pick a pinch of resin from your resin tank and grind it with your finger. If it crashes, that is fine mesh resin. If it forms a ball, it is standard resin.
