Straight Through Syrup Path- the Path of Least Resistance. The idea behind the SHURflo pump is to move the gas rather than the syrup. This feature has been built in the design of the pump, which provides a straight flow path for the product across the pump. This means the syrup has the least amount of restrictions possible. The fewer the restrictions there are means less pressure drop within the pump and greater CO2 savings. But more important the less pressure drop across the pump the more consistent the quality of the drink.

Twin chamber double diaphragm positive displacement with designed Hydraulic Advantage- that is given an inlet gas pressure the resulting force driving the syrup out is greater than the force applied by the gas. This is because the piston surface area to the "gas in" side of the chamber is greater than the effective piston surface area to the "syrup out" side. This difference gives the SHURflo pump a hydraulic boost.

Gas (CO2/Nitrogen/Air) Driven- The pump can be operated by either regulated CO2, nitrogen or clean compressed air. The compressed gas drives the pump and does not come in contact with the syrup. The minimum gas pressure is 20 psi (1.4 bar) and the maximum is 85 psi (5.8 bar). The figures below illustrate the flow of gas and flow of syrup when the pump is in operation.
Figure A
Figure B
Figure A - The CO2 enters the control cover through the poppet valve (which is open on this stroke) into the left CO2 chamber. The CO2 in the left chamber pushes the piston to the right, thus forcing out the syrup in the left liquid chamber (syrup under pressure), while suctioning syrup into the pump to the right chamber (syrup under vacuum). When the piston is fully extended, the switching system activates, closing the poppet valve and diverting the CO2 to the right chamber.

Figure B - The CO2 enters the control cover through the poppet valve. The valve blocks the passage into the left chamber, causing the CO2 to be diverted around the outside of the pump to the right chamber. The CO2 in the right chamber pushes the piston to the left, thus forcing out the syrup on the right side of the chamber (syrup under pressure), while pulling syrup into the pump to the left chamber (syrup under vacuum). When the piston is fully extended, the switching system activates, allowing CO2 to enter the left chamber, where the process in Figure A begins.
Automatic Demand- The pump operates only when syrup is needed. When the dispenser valve opens, creating a pressure drop, the pump operates to maintain syrup line pressure. The pump continues operating until the valve is closed and the syrup line pressure equals the gas pressure. At equalization, the pump stops.

Sold Out- The pump operates only when there is an adequate supply of syrup. Vacuum produced by the pump evacuates the syrup within the bag. Once the preset vacuum point is achieved and held, the gas supply to the pump is shut off, causing the pump to stop. When a new BIB is installed, the pump automatically starts and pressurizes the system. The benefit of the sold-out feature is that the outlet line to the dispenser always remains full of syrup.