The Deal

• $49 for carpet cleaning for three rooms of up to 150 square feet ($109 value)

Carpet Cleaning: Putting the Heat on Dirt

As techs re-fluff your carpets and your vacuum weeps in envy, learn how they work their magic with Groupon’s guide to steam cleaning.

Although steam can be an effective cleaning tool, when pros talk about steam-cleaning a carpet, they’re usually talking about a process technically known as hot-water extraction. That’s because steam—which occurs when water reaches 212 degrees Fahrenheit under normal conditions—is simply too powerful for many residential jobs, posing a risk of damage or shrinkage to some kinds of carpet fibers. Fortunately, water usually only needs to be heated to around 140 degrees to kill most of the microorganisms that can live in a carpet and cause odors. A skilled technician will know what range of temperatures is ideal for any given fiber.

Whether it’s a rolling model or a massive van-mounted machine, a carpet cleaner has three important elements: a heating device, water jets, and vacuum suction. As the water is heated, it will sometimes be mixed with detergent, but one of the benefits of steam cleaning is the fact that soap isn’t necessarily a must—pressurized jets can reach deep into fibers to get at grime. A vacuum hose then pulls most of the liquid back into the machine, though some dampness will linger in the carpet. Generally, after about three or four hours a carpet will be ready for you to walk on and set all your little army guys back in position.