A filler valve unit (1) for feeding a preset amount of filling liquid (3) into a container (6) having an outlet (4) for feeding out filling liquid and an outlet (11) for injecting gaseous fluid. The filler valve unit (1) comprises at least one stop element (14) forming a stroke limiter acting on the container (6). According to the invention, the stop element (14) is mobile and moves between at least two operating positions consisting of a first operating position wherein the stop element holds the mouth (5) of a container (6) at a preset distance from the outlet (4) and a second operating position wherein the stop element (14) holds the mouth (5) of the container (6) at a distance from the outlet (4) which is less than the preset distance.