If your water softener isn't working properly, one possible reason is that there is air in the system. Air can enter the system through a leak in the brine tank or by too much water flowing into the unit. Either way, purging air from your water softener is a relatively simple process.
To purge air from a water softener, start by turning off the power to the unit and then opening the drain line. Next, use a garden hose to siphon out any water that's left in the brine tank. Once the tank is empty, remove the lid and check for any cracks or leaks. If you find any, repair them with plumber's putty or epoxy resin.
Once you've repaired any leaks, rinse out the inside of the brine tank with clean water. Then, reassemble everything and turn on the power to the unit. Finally, run some water through it to make sure everything is working properly.