A water inlet assembly which is suitable for being used in a washing device comprising at least one inner chamber in which cleaning operations are performed, at least one water inlet opening allowing water intake to the inner chamber and at least a connection pipe conveying the water coming from a source into the said water inlet opening, which is configured to prevent a leakage of the contaminated water into the connection pipe and then into the water mains due to a reverse pressure that occurs during or after the water intake for washing and rinsing process and which comprises at least one body in the form of a hollow closed chamber having at least a first opening on at least one side thereof and configured to allow the connection between the said water inlet opening and the connection pipe; and at least one connection area located on a surface of the body, including at least one hole and configured to allow the connection of the body to the water inlet opening; characterized by comprising at least one cover assembly positioned to close the said first opening, at least a part of which is inserted into the body through the first opening, and including: - at least one cover body closing the said first opening, - at least one water inlet section extending from one side of the said cover body, which is located on a part of the cover body, which is in the form of a chamber and by which the water coming from the source is entered into the body and exited from the body by passing through the connection area, - at least a second opening located on the said water inlet section and allowing air to enter the interior of the water inlet section, - at least one condensation section in the form of a chamber, extending into the body from the other side of the said cover body, located on the other part of the cover body and being configured to condense a part of the steam that is formed in the inner chamber during a drying process performed in the inner chamber and being entered into the condensation section by passing through the water inlet opening and the connection area, and - at least a third opening located on a part of the said cover body where the condensation section is situated. - at least one cover body closing the said first opening, - at least one water inlet section extending from one side of the said cover body, which is located on a part of the cover body, which is in the form of a chamber and by which the water coming from the source is entered into the body and exited from the body by passing through the connection area, - at least a second opening located on the said water inlet section and allowing air to enter the interior of the water inlet section, - at least one condensation section in the form of a chamber, extending into the body from the other side of the said cover body, located on the other part of the cover body and being configured to condense a part of the steam that is formed in the inner chamber during a drying process performed in the inner chamber and being entered into the condensation section by passing through the water inlet opening and the connection area, and - at least a third opening located on a part of the said cover body where the condensation section is situated.