A fluid dispensing system and treatment system may be used to purge cleaning fluids from lumens of an endoscope. A portion of a fluid chamber can be filled with liquid by providing liquid through an inlet of the fluid chamber. A sealing pressure can be generated with gas in the fluid chamber and additional filling of the fluid chamber through the inlet can be limited. Liquid from the fluid chamber can be dispensed responsive to the sealing pressure. The dispensing can comprise expelling liquid through an outlet of the fluid chamber utilizing gas. The gas may be pressurized in multiple reservoirs, each one being dedicated to a purge line of the treatment system.
