Preventing the flow of the ambient air into the cabinet (2) by closing the discharge pipe (4) under normal conditions, balancing the cabinet (2) interior pressure by opening into the cabinet (2) from the side of the ambient air when the cabinet (2) interior pressure drops and discharging the water in the cabinet (2) especially after defrosting, outside of the cabinet (2) is accomplished by utilizing the valve (5) which is the object of the present invention.
