I have never had a water softener. New house has one. I need to replace filter on a Water Boss system. I need a primer.

Bob, I don't think filter replacement is necessary. Is it giving you trouble ? Usually, these built-in filters last for the lifespanof the softener. That's why you have backwash.

The backwash is usually programmed into the unit and unit backwashes automatically as preset. I am sure, you can also do it manually. Just open the lid and follow the instruction.

Please, post model of your unit so I can take a look at the manual. There are several WaterBoss models on market.