A reduced-pressure system for delivering reduced pressure for medical purposes to a desired site and to receive fluids in one instance includes a reservoir having an interior space operable to contain the fluids. A reduced-pressure delivery conduit is placed in fluid communication with the interior space for delivering the reduced pressure to the desired site. A source conduit and a pressure sensor conduit are placed in fluid communication with the interior space. A pressure sensor is placed in fluid communication with the pressure sensor conduit. A reduced-pressure source is placed in fluid communication with the source conduit. A reduced-pressure control unit is associated with the pressure sensor and the reduced-pressure source and is operable to receive pressure data from the pressure sensor and supply data from the reduced-pressure source and to determine when a reservoir-full/blockage condition exists. Other systems and methods are presented.