Facility and method for producing a carbonated beverage

Provided is a facility for producing a carbonated beverage that can efficiently readjust a product liquid in which a gas volume of the product liquid is out of a specified range. A facility 1 for producing a carbonic acid beverage includes: A brewer 10 that generates a mixed liquid of raw material water and raw material syrup and includes a mixed liquid tank 16 for storing the generated mixed liquid; and a carbon dioxide gas supply unit 10 that generates a product liquid by dissolving carbon dioxide gas in the mixed liquid supplied from the mixed liquid tank, A carbonator 20 having a product liquid tank 25 that is in a carbon dioxide atmosphere, a filler 30 that fills the container with the product liquid supplied from the product liquid tank, and a circulation path that returns the product liquid to the product liquid tank from between the carbonator and...