Abstract: A syrup delivery system delivers flavored syrup. A solenoid introduces air into the system and into an inlet of an exhaust diverter including a flexible diaphragm. The air exits the exhaust diverter through an outlet for entry into a syrup valve that dispenses the syrup. After dispensing of the syrup, the solenoid blocks air from entering the system. The air from the syrup valve reenters the exhaust diverter through the outlet. The air exits the exhaust diverter through the contaminated air exhaust. The air pushes on the flexible diaphragm, which contacts a seating surface around the inlet, preventing the air from exiting the exhaust diverter through the inlet. The remaining air in the system passes into the expansion tank and is diffused, causing any contaminates in the air to fall to the bottom of the expansion tank. The exhaust air is also subjected to a turbulent air flow path in the expansion tank that further separate any contaminants from the air.