Abstract: The invention concerns a central vacuum cleaning system for vacuum cleaning ducts permanently installed in buildings. The device has three connected sections which form the integral unit. The top section contains the suction turbine, its motor and an exhaust outlet for clean air. The center section contains air baffles, a perforated circular conduit below the air baffles and for dispersing water, an angled inlet conduit for dust-laden air, and a water level sensor. The bottom section contains a water outlet, a flexible sleeve valve, the outlet end of the angled inlet conduit from the center section, a water reservoir with a water level above the outlet end of the inlet conduit and substantially even with the water outlet, and a drain plug. Dust-laden air bubbles through water in the reservoir. The dust-containing water is automatically flushed by electronic control circuitry coordinating the filling and evacuation sequence.