Nadair ST-600-18B Top-Fill Bagged Central Vacuum, 600 AW, 2,500 Sq Ft

The ST-600-18B is Nadair's top-fill, bag-based power unit, rated at 600 air watts for homes up to 2,500 square feet. Top-fill bagged means debris collects in a disposable bag that loads and comes out from the top of the canister, rather than a reusable bin emptied by hand or a filter-only design that holds dust loose inside the housing.

The bag-based design's main advantage shows up at service time. Instead of opening a bin and dealing with a cloud of loose dust, the filled bag lifts out sealed and goes straight into the trash, which matters for anyone in the household sensitive to dust or allergens during emptying.

At 600 air watts and a 2,500 square foot rating, this unit is sized for a smaller home, a townhome, or a condo rather than a large single-family house, and its scale reflects that: it is built to tuck into a tighter mechanical space than the larger units in a typical lineup require. That smaller footprint also means less weight and bulk to maneuver when the unit first goes in, which matters in a tight utility closet where working room is already limited before the unit itself takes up any of it.

• Model: Nadair ST-600-18B
• Rated output: 600 air watts
• Coverage: homes up to 2,500 square feet
• Collection: top-fill design, 3.2-gallon disposable bag
• Motor: 5.7-inch two-stage tangential by-pass
• Performance: 127 CFM airflow, 140.9-inch water lift

Budget for replacement bags as a recurring supply item with a bag-based unit, and confirm the 2,500 square foot coverage rating comfortably exceeds your home's finished square footage before ordering. If anyone in the household has dust or allergy sensitivity, weigh the sealed-bag emptying process against the lower ongoing cost of a filter-only unit before choosing between the two collection styles.