Today's
TECHNOLOGY AND YOU

Q: I vacuum often because of my children's allergies. I have considered installing a central vacuum system for extra powerful deep cleaning. Will running one use much more electricity.? Which ones are best? • G. S.

A: Central vacuum cleaners provide the best deep cleaning for dust-and-allergen-free indoor air. The dust and dirt are sucked away to a remote super powerful suction unit (power unit). You can install the power to exhaust the air outdoors or indoors through special filtration systems. Vacuuming is so quiet that it will not wake someone sleeping, interrupt a telephone conversation or drown out a baby crying.

Installing one yourself is usually a simple weekend job, even in most two-story houses. Easy-to-cut two-inch plastic pipe is used to connect the wall inlets to the remote power unit. With a typical 32-foot cleaning hose, a 1,400-square-foot house needs only two wall inlets. A 2,100-square-foot house needs three inlets and a 2,800-square foot house needs four inlets.

Running a super-powerful (some have two or three suction motors combined) central vacuum cleaner actually can use less electricity overall than a standard portable vacuum. Even though the most powerful central power units use up to 13.5 amps of electricity, you will have to vacuum less often.

The deep cleaning removes more dirt and allergens each cleaning and the dirty air is exhausted outdoors or filtered to the basement or garage. At an electric rate of 10 cents per kilowatt-hour, a super-powerful 13.5-amp unit costs about 8 cents per 30 minutes of use.

All of the electricity used to operate the central vacuum cleaner ends up as heat inside your house anyway. If you use electric heat in the winter, running the central vacuum reduces the heating load on your system by the same amount of electricity the vacuum uses. To save the most electricity, vent the power unit indoors. The outlet air is very clean.

Deep cleaning carpet and furniture provides a hidden savings. Residual dirt left in fabrics is a primary cause of wear. With deep cleaning, carpeting and furniture will last longer and look better.

Most central vacuum cleaner kits include every part—elbows, screws, wires, fitting, etc.—except for the readily available 2-inch PVC pipe. Mount the power unit (only 3 feet high) on a wall near an electric outlet. Run the main PVC pipe under the floor or in the attic with branches to wall inlets. You can easily run it to a second story through a closet, cold-air return duct, laundry chute or behind built-in appliances.

There are several filtration designs. One type uses a large disposable paper filter bag. Since it is big (up to 6 gallons), it has to be changed only twice a year. These special high filtration bags are very effective for allergy sufferers.

Another common design uses inverted cyclonic runnel cone action. The internal shape of the unit causes the incoming dirty air to spin around very fast inside the power unit. Centrifugal force pushes dust and dirt out to the sides and it drops into a canister. The canister must be emptied three to four times per year. Some of the most effective types use a combination of bags, filters and cyclonic action. If you vent the exhaust from the power unit to outdoors, the type of air cleaning method is not critical. Its main purpose is just to protect the suction motors from excessive dirt Cleaning power of central vacuum systems is determined by suction (inches of water lift) and air flow rate (cubic feet per minute, or cfm). Through engineering calculations, these figures result in a cleaning power rating called air power watts. Some models have as much as 160 inches of lift and 245 cfm and more than 500 air watts. Generally, the higher the air watts, the better the deep cleaning.

All central vacuum systems use safe low-voltage wires to automatically turn on the central power unit when you push the hose into the wall inlet For the simplest wiring, just tape the low-voltage wire to the 2-inch pipe. A new convenience feature is a power touch handle with a built-in on-off switch. This allows you to switch off the power unit without having to pull the hose out of the wall.

Another convenience feature is an optional Vac-Pan. It is a long flat inlet mounted in the baseboard. On smooth floors, like a kitchen, you just sweep dirt over to the Vac-Pan and it is sucked away. If you need a powerful vacuum in your workroom in a garage or basement, locate the power unit there. Select a model with a built-in inlet on the power unit This inlet has super-powerful suction since there is no long pipe resistance.

Write for Utility Bills Update Bulletin No. 740 showing a buyer's guide of 11 central vacuum cleaner manufacturers, and listing types of filtration, cleaning power, features, installation layouts and prices. Please include $2 (with checks payable to Jim Dulley) and a business-size SASE, and send to Jim Dulley, Illinois Country Living, P.O. Box 3787, Springfield, IL 62708.

James Dulley is a mechanical engineer who writes on a wide variety of energy and utility topics. His column appears in a large number of daily newspapers.

Copyright 1996 James Dulley

20 ILLINOIS COUNTRY LIVING APRIL 1997