Abstract: A carbonation machine may include a carbonation head with a bottle holder configured to hold a bottle with water to be carbonated and inject carbon dioxide into the bottle; and a safety dual valve assembly comprising a first spring operated piston and a second spring operated piston, for releasing excess pressure when the bottle is held by the carbonation head, wherein the first spring operated piston is configured to release excess pressure at a first pressure threshold level and wherein the second spring operated piston is configured to release excess pressure at a second pressure threshold level, wherein the first pressure threshold level is lower than the second pressure threshold level.

Abstract: A carbonation machine includes a carbonation head to sealingly couple to a bottle filled with liquid to be carbonated; a piping to introduce and compress carbon dioxide into a space within the bottle above a top surface of the liquid to a predetermined pressure level when the bottle is coupled to the carbonation head; a stirrer to stir the liquid to enhance absorption of carbon dioxide in the liquid when the bottle is coupled to the carbonation head; and a manually operated valve mechanism configured to be moved to any position between a closed position to an open position for user-controlled release of pressure within the space.