Dual-motor vacuums have long been an industry standard, and more often than not, these machines are the only choice for cleaning veterans. Dual-motor vacuums are built with one motor dedicated to driving the brush and a separate motor dedicated to suction. Single-motor vacuums have one motor for both functions.
In most applications, single-motor vacuums perform fine and are adequate to meet the cleaning needs. However, there are some definite differences between single-motor and dual-motor vacuums, especially when it comes to longevity, productivity, and performance.
In terms of longevity, most commercial single-motor uprights will last three to four years with proper care and maintenance. In contrast, most commercial dual-motor uprights will last six to nine years. Much of the increased life is due to that fact that there’s less strain on the motors, since each process in the vacuum operates off of a dedicated motor, rather than having one motor that handles both processes.
The level of a vacuum’s productivity is rarely considered by users because the operation of a dual-motor vacuum is often confused with that of a single-motor vacuum. A single-motor vacuum is designed to work in a back-and-forth motion that all of us are familiar with. This “push-pull” motion has the user covering many of the same areas with each stroke.
In contrast, a dual-motor vacuum is designed to be run in a single pass motion that is similar to the passes that would be made with a lawn mower or a wide-area vacuum. According to the ISSA, this leads to a 15-percent increase in productivity over a similar sized single-motor upright. In this regard, dual-motor vacuums will more than pay for themselves over their lifetime.
Consider a basic scenario. According to ISSA 540 cleaning times, an 18-inch single- motor upright vacuums 3,448 square feet per hour, while an 18-inch dual-motor upright vacuums 4,000 square feet per hour—a 15-percent increase in production. When vacuuming that 4,000 squarefoot area daily over the course of the year, your labor costs for both machines can be calculated as follows:
• Single-Motor Vacuum: 4,000 square feet/ 3,448 square feet per hour = 1 hour, 9 minutes to vacuum the area. At $15.00 per hour for labor that means it costs $17.25 per hour in labor cost. $17.25 x 260 times per year = $4,485.00 in total labor costs to vacuum that area with a single-motor upright.
•Dual-Motor Vacuum: 4,000 square feet/4,000 square feet per hour = 1 hour to vacuum the area. At $15.00 per hour for labor that means it costs $15.00 per hour in labor cost. $15.00 x 260 times per year = $3,900.00 in total labor costs to vacuum that area with a dual-motor upright.
• Bottom line: By using a dual-motor device, you’ll see savings of $585 per year in labor costs on just a small 4,000 square-foot area
When it comes to performance, the whole purpose behind vacuuming is to remove dry soils from the carpet, which improves the indoor environmental quality of a facility and reduces the wear and tear that soils cause to the carpet fibers. While most single-motor uprights do a very good job at removing soil from the carpet, dual-motor vacuums are designed for maximum performance in this area.
Test results have shown that for the most thorough removal of dry particulate soils a dual-motor vacuum outperforms an upright vacuum. So not only are dual-motor vacuums more efficient in terms of labor, they are also generally more effective in terms of soil removal Dual-motor vacuums are designed to be used in high traffic areas where maximum soil removal is critical.
Dual-motor vacuums are ideal for applications such as entryways, lobbies, elevators, and areas of transition between hard surfaces and carpeting.
Finally, due to the importance of removing dry particulate soils before any moisture is added to the carpet through the cleaning process, dual-motor vacuums should be used to vacuum areas being cleaned. The more soil that can be removed before cleaning reduces the amount of soils that can wick to the surface and leave a dingy, muddy appearance during the drying process.
Richard “Bo” Bodo is the Director of Business Development at Windsor Industries, an IICRC Master Textile Cleaner, and a contributor to industry standards, training programs, and publications.