QD Max and QD Lite most often (more than 90% of units sold) use a venturi to create suction to draw chemical products into the batch. However, SureFire offers both QD Max and QD Lite in a pump suction configuration.
Venturi Suction – Transfer pump is located on the QuickDraw inlet. It pushes water across a venturi to create suction which draws chemical products through the mass meter and into the batch.
Pump Suction – Transfer pump is located on the QuickDraw outlet. Suction from the pump is utilized to draw chemical products through the mass meter and into the batch.
Reasons to consider a Pump Suction QuickDraw:
You want the ability to pump chemical into a batch with no water / carrier being pumped. With a venturi, water is always being pumped at about 40 GPM to create chemical suction.
You want to mix batches with less than 70% carrier.
Reasons why more than 90% of QuickDraw's use a venturi:
With a venturi, only the carrier passes through the pump, never chemical. This means less places for chemical to sit and pose a contamination risk.
The venturi is just a simpler choice. On a pump suction QuickDraw you will have to adjust the setting of the carrier regulating valve to balance carrier and chemical flow.
See QD 3000 Max, QuickDraw Max Gen 2, or QuickDraw Lite for most product information and talk to SureFire or your SureFire QuickDraw Dealer about the pump suction option if it fits your needs.