How Water Softening Systems Work

Hard water passes through the media tank that contains resin beads coated with sodium ions. The calcium and magnesium ions are exchanged for sodium (or potassium) ions, thus softening the water.

When the beads have trapped the hardness and need to be regenerated, the control valve charges them with brine (salt and water solution) from the brine tank. As regeneration occurs, calcium and magnesium (hardness) ions are freed from the beads, replaced with sodium or potassium ions; and the system is ready to soften water again.