While many Americans are unfamiliar with central vacuums, they are not new inventions; the idea dates back as far as the 1850s in Sweden, where horse-powered fans were used to create suction through in-wall plumbing. Horses were later replaced by servants, who pumped giant bellows or pedaled stationary bicycles, until electric motors eventually took over. Shortly thereafter, however, portable vacuum cleaners became available, and central vacuum systems were largely forgotten due to their relative expense. Their hibernation ended by the 1990s when growing house sizes and concerns over air quality combined with the availability of cheaper plastic piping, more powerful motors and refined filtration systems. Yet, even today, American homes are dependent on portable vacuum cleaners, in contrast with Canadian and Scandinavian homes, where central vacuum systems are more common.
Central vacuum systems boast some advantages over portable units, some of which are as follows:
- They are long-lasting. Their motors can handle more usage than typical portable units. Warranties, too, are usually longer for central units.
- They are quiet. Because the motor is located outside the living area, users are not subjected to noise created by the motor, which can be excessive and stressful.
- They can be retrofitted into older houses, or built into new construction.
- They are a good investment. Just as a kitchen renovation or new deck will make a home more valuable, many buyers will pay extra for a house equipped with a central vacuum.
- They are hypo-allergenic. Unlike portable vacuums, which recycle air back into the room, dust-laden air is blown into the outdoors from central vacuum systems. One comprehensive study conducted at the University of California at Davis' School of Medicine compared portable to central units and concluded that “a central vacuuming system would best provide [allergen removal] as it would be installed outside the living area of the dwelling and/or vented outdoors."
- The system is easy and safe to use. There is no heavy equipment to carry from room to room, and no electric cords to trip over or catch on furniture.
- cyclonic, in which air is spun in a canister and exhausted to the outdoors. Location is critical for these units, as it is possible for exhausted, debris-laden air to find its way back into the house through open windows. The filter must be removed and cleaned periodically;
- inverted filter, in which the dirt enters the vacuum canister amidst a tornado-like swirl of air. The canister must be emptied periodically, and always outside of the home. Allergy sufferers may find disposal unpleasant, as mold and other debris become airborne; and
- disposable bag, in which dirt is sucked into a paper bag in the same fashion as for portable units. This is perhaps the cleanest and most hygienic method available, as mold spores, bacteria and other debris are physically separated and stored in a bag from which they cannot escape.
- price. A good system can cost $1,500, which is significantly more expensive than even premium portable vacuum cleaners;
- damage caused by items sucked up inadvertently. With greater power comes higher risk that large items will be sucked up, potentially causing damage to the unit. Tales abound of units becoming jammed or broken when they swallow, often at the hands of children, broken jars of jelly, toilet water, and even pet birds. Portable units are usually too weak to readily suck up items that can cause them to break;
- a system compromised by weak suction. Such a problem may be due to obstructed pipes or exhaust, an excessively dirty filter, or a full canister that needs to be emptied. If the unit does not operate at all, the motor might be broken, a breaker may have tripped, or the wiring may be defective.