The industry norm is to install a 5-micron sediment filter before the water softener to protect
your water softener from dirt, sand, and rust partials which could lead to premature failure.
The industry norm is to install a 5-micron sediment filter before the water softener to protect your water softener from dirt, sand, and rust partials which could lead to premature failure.
Always follow the PRE-FILTER recommendations of the water softener manufacturer for the micron rating requirement, some softener companies may require a lower 1-micron rated cartridge, while others may allow a 10-micron cartridge. Failure to follow the manufactures pre-filtration requirements may void the softener’s warranty. We recommended to read the softener warranty to ensure your installation will meet the requirement to ensure you are covered.
Make sure to select a filter cartridge that is large enough having a sufficient flow rate capacity
to avoid causing unnecessary drops in your water pressure. A rule of thumb is a minimum of 2 times the desired flow. This can vary depending on conditions. For example, clean filter flow rate of 1.5 times is sufficient if sediment load is light, but up to 3 times if sediment load is heavy. See #4 of the article at the link below.
https://support.boshart.com/what-are-the-required-steps-to-properly-select-a-water-filter
If your water has a heavy load of sand or visible grit, it is recommended to install a pre-filter, there are two typical options.
The installation of a traditional whole house filter housing with a sediment filter cartridge, rated for 20 to 50 microns to remove most of the coarser particulate. This will extend the time between cartridge change-outs by preventing the finer 5 – 10-micron filters from clogging too quickly.
Typical Two-Stage Filter Set Layouts
Standard Municipal / City Water:
City water rarely has large, chunky debris, for this reason a two-stage filter system may not be required. A single Point -Of-Entry (POE) whole house water filter with a 5-micron filter effectively stops fine silt and cloudiness before it reaches the softener resin. NOTE: Always verify the required micron rating with softener manufacturer.
Well Water: Well water often requires a two-stage pre-filtration setup (two filters plumbed in series) to avoid choking your water pressure.
First Stage:
OPTION #1 - A traditional whole house filter with a coarse micron rating, a washable pleated polyester 30-50-micron may be a viable option, spun poly filter cartridges are also a very economical solution
OPTION #2 - A Spin-Out filter that separates coarse sand. Note the finest mesh of 1000 only filters out particulate down to 15 microns, this is not sufficient protection for your water softener.
Second Stage:
A whole house 5-micron finishing filter polishes the water and must be installed before the softener to effectively trap fine silt, dirt, and rust that will pass through the Stainless Steel mesh of a Spin-Out Filter or the coarse 20–50-micron sediment cartridge. A 5-micron filter is the industry standard as they typically do not cause a severe drop in water pressure.