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CO₂ Sensing

Purpose

Plants consume CO₂ during photosynthesis. In a sealed grow space, CO₂ can become depleted below ambient (~420 ppm), limiting growth. Monitoring CO₂ allows the exhaust fan to introduce fresh air when levels drop.

Hardware

  • Sensor: TBD (e.g. MH-Z19B NDIR, Sensirion SCD30)
  • Interface: TBD (UART / I²C)
  • Placement: at canopy level; away from direct airflow to avoid dilution artifacts

Integration

  • Polling interval: TBD
  • Target range: TBD (ambient ~420 ppm; enriched grows may target 800–1200 ppm)
  • Low CO₂ triggers Air Regulation actor (fresh air exhaust cycle)

Notes

  • NDIR sensors (MH-Z19B) require periodic auto-calibration to outdoor air or manual baseline correction.
  • CO₂ enrichment (injection) is a future direction — not in current scope.

Sources