A whole-home water softener has a long service life, but performance depends on water chemistry and maintenance. Common issues include control valve failures, brine injector clogging, leaks at fittings, and resin bed degradation that reduces softening capacity.
Repair is often worthwhile because many problems are modular and serviceable-cleaning injectors, replacing a motor/valve, or fixing plumbing connections can come in under the threshold and restore performance. Replacement becomes more attractive when the resin bed is exhausted or fouled (softness drops even after regeneration), the cabinet shows cracking, or multiple valve components fail in succession, since the combined service cost can approach the threshold and reliability may remain shaky.
Also consider salt and water usage: newer models may be more efficient, so replacement can pay back over time in operating costs. If hard water is damaging fixtures or appliances, restoring reliable softening is usually worth prioritizing.