Applicant has created systems, methods, and apparatuses for controlling the power supply of a vacuum cleaner motor. The systems and apparatuses include pressure taps to detect a pressure differential within a vacuum cleaner, a float that adjusts depending on an amount of liquid stored, and a power switch that toggles based on the pressure differential created by the position of the float. Alternatively, the float can be replaced by an air chamber so that the pressure differential is created by liquid rising above the volume of air trapped in the chamber. The method can include interrupting the current supplied to an electrical circuit of a power switch based upon a pressure differential created within the vacuum. By controlling the power supply to a vacuum cleaner motor based on a pressure differential created by the amount of liquid stored within the vacuum cleaner, the vacuum cleaner can automatically disable the vacuum cleaner's motor as the vacuum approaches its maximum liquid capacity.