The Principle Operation of a Backflow Prevention Device for Beverage Dispensing Equipment – General Specifications

The backflow prevention for beverage dispensing equipment (BPBDE) is a backflow prevention device used for beverage dispensing equipment to prevent carbon dioxide gas and carbonated water generated by a post-mix beverage system from enter the potable water system. The BPBDE consists of two independently acting check valve biased to a normally closed position and a normally open atmospheric port located between the check valves. The atmospheric port is designed to vent liquids, gases, or both under backpressure conditions if the second check fails to close. The BPBDE is designed to operate under a continuous or intermittent pressure conditions and can be installed vertically or horizontally. Typically, the BPBDE is equipped with a strainer or integral strainer screen at the inlet. The BPBDE shall be constricted of corrosive resistant material such as plastic or stainless steel since the substances downstream are very acidic. The BPBDE can be used on non-carbonated beverage systems as well. The BPBDE is designed for supply pressure up to 150 psi and temperature from 33 degrees to 130 degrees. The BPBDE is a non-testable device and shall comply with ASSE Standard 1022.

Until recently non-vented double-check valve ASSE 1032 compliant backflow prevention devices were approved for the protection of the potable water system for carbon dioxide gas and carbonated water by the major plumbing codes. The ASSE 1032 compliant backflow prevention device does not have an atmospheric port therefore, there is no way of knowing if the second check was operating properly during a backpressure condition. Because the ASSE 1032 compliant backflow prevention device does not have a visual indication of a failure of the second check valve during a backpressure condition, the industry plumping codes are now requiring backflow prevention devices conforming to ASSE 1022 to be installed on potable water systems connected to beverage dispensers.