• High and low vent openings must be separated by a minimum of 10 vertical feet.
  • The high and low vents should be of the same capacity.
  • A low vent is installed through an offset adapter at the end of each row, Section or Basic Serial Bed.
  • Low vents should be a minimum of 3 ft. high or above snow line.
  • Alternatively, the low vent may be attached to the d-box and the high vent may be attached to the end of the last AES or Enviro-Septic® row. If this configuration is used in cold climates, the d-box must be insulated to prevent it from freezing.
  • A high vent is installed through an unused d-box outlet (see diagram below).
  • Sch. 40 PVC or equivalent should be used for all high vents.
  • All high vents should be at least 4 in. in diameter.
  • All vents higher than 3′ should be anchored.

Differential Venting for Pump Systems