Buffer Box

Buffer Box


  • Receives and holds waste water from fixture drains
  • Meters quantity of water per discharge cycle
  • Sends head pressure signal to Activator
  • Provides atmospheric air intake for discharge cycle
  • Prevents backflow into fixtures in the event of system malfunction
SKU: 2801055 Categories: , ,


The Evac Buffer Box is a component that receives waste water from fixture drains. It’s one of the key components that comprise an Evac riser along with an Activator, Discharge Valve, BVP Valve, Mini-Check Valve, and Vacuum Hose.

When waste water from a hand sink or a refrigerated display case enters the Buffer Box, the water begins to create a head pressure in the Sensor line (Vacuum Hose). When the head pressure reaches the preset level, the Activator opens the Discharge Valve and air pushes the water up the Riser and through the Discharge Valve, into the Vacuum Piping Network. It is sized to handle the intermittent heavy flow generated during a wash-down of a display case (flow rates up to 6.0 gpm).

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