NuTone® Residential Central Vacuum System Power Unit, 550 Air Watts 4.0 (8) 4.0 out of 5 stars. 8 reviews Model: PP5501 View NuTone® Residential Central Vacuum System Power Unit, 650 Air Watts 3.0 (17) 3.0 out of 5 stars. 17 reviews Model: PP6501 View Central Vacuum ...