Time between maintenance: filter element replacement

  • Intervals between replacement of major components (filter element) meet user expectations for device capacity (volume), service life (time), and cost.
  • Quality and safety of treated water remain within acceptable limits between replacement intervals.

Key indicators

  • Consumers demonstrate acceptance of the ratio between recurring costs and initial purchase price (by purchasing replacement components at suggested intervals).
  • Replacement frequency meets consumer expectations for durability and economy (based on analogous products).
  • Filter element threshold capacity: 2000 L.
  • Filter element most desirable capacity: 4000 L.
  • Treated water quality does not exceed safety limits in the intervals between filter element replacement.

Notes and exceptions

  • Volume-based intervals for better element replacement may be difficult for users to measure in the absence of more explicit indicators.
  • Low-income consumers will likely expect product components to last several multiples of their advertised capacity or life.
  • Users may tolerate higher replacement frequencies for very low-cost replaceables such as paper pre-filters or chlorine tabs.
  • Replacement frequencies should align with cultural norms (holidays, religious events, agricultural cycles, seasons, etc.) that are familiar and easy for users to remember.

Supporting evidence