Filling system

A filling system comprising:

• a conveyance chamber that conveys vessels;
• a plurality of filling chambers provided with filling heads for filling contents into the vessels;
• an intermediate chamber provided between the conveyance chamber and at least one of the plurality of filling chambers;
• a pressure controller that controls the pressure conditions of each of the:
• conveyance chamber, the at least one of the plurality of filling chambers, and the intermediate chamber;
• and
• an opening/closing door configured to separate the at least one of the plurality of filling chambers from the conveyance chamber by closing an opening provided between the at least one of the plurality of filling chambers and the conveyance chamber,
• wherein, in a state in which the opening is closed by the opening/closing door, the conveyance chamber is provided on one side of the door and both the intermediate chamber and the at least one of the plurality of filling chambers are provide on other side of the door such that the at least one of the plurality of filling chambers is capable of being washed while the opening is closed, and wherein,
• in the state in which the opening is closed by the opening/closing door, the pressure controller is configured to control the pressure of the intermediate chamber to become lower than the pressure of the conveyance chamber and the at least one of the plurality of filling chambers.