Abstract: A cyclonic power wash system uses high pressure, high temperature water for selectively cleaning large, flat, concrete or asphalt surfaces. The sprayed water is reclaimed by vacuuming it through holes in the bottom of a reclamation ring attached to the underside of the mobile cyclone sprayer, filtering the vacuumed water and returning it to a storage tank for re-use by the system. The filtration tank initially filters out large matter in an inlet trough and smaller matter in a plurality of cascading chambers. A rotary union in the sprayer prevents the water, passing from the inlet of the rotary union to the discharge thereof, from leaking through or around a seal formed by pressing together a pair of hard, durable sealing surfaces, for example, silicon carbide, one of which is non-rotatably slidingly received in an upper recess of the union's fixed housing and the other, affixed to a spindle rotatably received and retained in a lower recess of the housing.