What step in the water softener regeneration process ensures the removal of accumulated minerals?

The step in the water softener regeneration process that ensures the removal of accumulated minerals is backwash. During backwash, the flow of water is reversed through the resin bed. This process helps to dislodge trapped particles, sediments, and accumulated hardness minerals such as calcium and magnesium that have been collected by the resin during the softening cycle.

Backwashing is crucial because it restores the effectiveness of the resin, ensuring that the water softener continues to function efficiently. The flow of water is directed upward, which helps to suspend the debris and carry it away from the resin, thereby cleaning it. As a result, when the system resumes normal operation, it can effectively soften water by exchanging the hard minerals for sodium ions, providing optimal performance and longevity of the equipment.

The other options, such as slow rinse, rapid rinse, and service, all play roles in the regeneration cycle, but they do not specifically address the removal of accumulated minerals in the same way that backwashing does.