Q Are the carpet steamer/cleaners that you can rent at the grocery store worth it?
A It is possible to clean carpet reasonably well with a machine you rent. That said, you should also recognize that a good professional probably would do a better job. And if you anticipate tackling the job frequently on your own, you might be better off buying a deep-cleaning machine, which works similarly to the rental machines.
With all of these options, the basic cleaning method is the same. Although it's often called steam cleaning, the process doesn't use actual steam. First a solution of detergent and water is spread over the carpet and worked into the fibers. Then it is rinsed out -- along with the grime -- by vacuuming up as much moisture as possible. (Other approaches to carpet cleaning, such as buffing fibers with absorbent pads or working in absorbent powder and then vacuuming it out, don't work as well, according to research done by Shaw Industries Inc., the world's largest carpet manufacturer.)
Professionals with truck-mounted equipment have the edge in several ways. Because they clean carpets day after day, they aren't as likely to make mistakes such as using too much detergent or neglecting to rinse away all residue. Also, the trucks deliver hot water, which boosts the detergent's effectiveness. With a rental machine, the best you can do is to pour hot water into the mixing tank and hope it doesn't cool off too much as you clean. Finally, professionals benefit from having more powerful vacuum systems. Because they remove more water, it's possible to rinse more thoroughly. The amount of water flowing through carpet fibers is the most important factor that determines whether a cleaning is thorough, Shaw's researchers found. Plus, the professional vacuums leave the fibers dryer, so the room can get back in use faster.
However, getting a professional cleaning is relatively expensive compared with tackling the job yourself with a rented machine. Two years ago, as Consumer Reports magazine was testing deep cleaners, researchers also evaluated one professional service and one nationwide rental company's machines. The pro did an "excellent" job, while the rental machines were just "good." Yet Consumer Reports, always on the hunt for bargains, still saw value in using a rented machine. To clean two rooms and a hallway, the professional charged $181. Renting a machine for a day cost only about $20.
One factor that dragged down the score for the rental machines: Their quality varied considerably. If you're a novice at carpet cleaning, this is a big issue. If a machine not in good repair dumps too much detergent onto the carpet, for example, you might just keep going, assuming that's what it's supposed to do.
Buying a deep-cleaning machine gets around this problem, assuming you take the time to read the directions and take reasonable care of the tool. Consumer Reports tested three deep cleaners and found that the Hoover Steam Vac V2 and the Bissell 7920 ProHeat Pro-Tech were "very good," just a notch below the professional cleaner's score. Each model cost about $250.
If you compare all the numbers, you realize that you could rent a machine nine times for the price of one professional cleaning for part of a house. And for not all that much more, you could buy a home machine to use whenever you want. So it's a good question whether frequent cleaning with a "very good" or even a "good" machine leaves the carpet cleaner than if you save up for periodic professional cleaning, even if it is more thorough.
Carpet manufacturers generally recommend professional cleaning of carpets every 12 to 18 months. But if you have indoor pets, track in oily dirt from a garage floor, or find lots of sticky things spilled on your carpet, renting a machine or buying one for interim cleanings makes sense. If, after several DIY cleanings, the fibers don't seem to be as clean as they once were, you can always call in a pro for a more thorough job.
If you do proceed to clean on your own, with either a rented machine or one you buy, a few steps can make all the difference in how the job turns out. Use only the detergent recommended for the machine, and never use more than the label recommends. A more concentrated formula won't clean better; it will just leave the carpet fibers sticky.
Many professionals mist a pre-treatment solution onto the carpet, which allows a longer time to break down oily compounds. Then they run only clear water through the machine. You might experiment with the same approach. Or, if you want to minimize the use of cleaning products in your house, try using the machine with only plain, hot water, especially if you still plan a professional cleaning periodically.
Before you begin, make sure that you have one or more good fans available so that you can ensure speedy drying even if something goes wrong. With properly functioning equipment, the carpet should dry within four or five hours; if it takes more than 24 hours, you risk getting mildew growth in the backing.
By Jeanne Huber
Special to The Washington Post