A reduced pressure delivery system is provided and includes a primary manifold, a blockage prevention member, and first and second conduits in fluid communication with the primary manifold. The primary manifold includes a flexible wall surrounding a primary flow passage and is adapted to be placed in proximity to a tissue site. The blockage prevention member is positioned within the primary flow passage. A plurality of apertures is disposed in the flexible wall to communicate with the primary flow passage. The first conduit is fluidly connected to the primary flow passage to deliver reduced pressure through the primary flow passage and the plurality of apertures. The second conduit includes an outlet proximate the primary flow passage or an outlet of the first conduit to purge the primary flow passage or first conduit to prevent blockages.