Systems, methods, and apparatuses for irrigating a tissue site are described. The system can include a tissue interface and a sealing member configured to be placed over the tissue site to form a sealed space, and a negative-pressure source fluidly coupled to the sealed space. The system includes an irrigation valve having a housing, a piston disposed in the housing, a fluid inlet to fluidly couple a fluid inlet chamber to a fluid source, and a fluid outlet to fluidly couple a fluid outlet chamber to the sealed space. A piston passage extends through the piston and fluidly couples the fluid inlet chamber and the fluid outlet chamber, and a biasing member is coupled to the piston to bias the irrigation valve to a closed position. The negative-pressure source is configured to move the piston between the closed position and an open position to draw fluid to the sealed space.