Carpet cleaning

Carpet cleaning, for appearance, and the removal of stains, dirt, and allergens is done through several methods. Clean carpets are recognized by manufacturers as being more visually pleasing, potentially longer-lasting, and probably healthier than poorly maintained carpets.

Although there is an actual steam cleaning industrial process, in the context of carpet cleaning, "steam cleaning" is, in fact, hot water soil extraction cleaning, which is professionally known as HWE. The hot water soil extraction cleaning method uses equipment that sprays heated water, sometimes with added cleaning chemicals, on the carpet. Simultaneously, the water is vacuumed up, along with any dislodged and dissolved dirt. Many carpet manufacturers recommend professional hot water extraction as the most effective carpet cleaning method which also provides a deeper clean. Actual steam could damage man-made carpet fibers and change the characteristics as they are usually set using heat. Natural fiber carpets such as wool can shrink, Velvet piled carpets and Berber carpets will become fuzzy which is known as pile burst.

Hot water extraction equipment may be a portable unit that plugs into an electrical outlet, or a truck mount carpet cleaner requiring long hoses from the truck or trailer. Truck mounted equipment may be used where electricity is unavailable (e.g. if electrical service was terminated). Truck mount carpet cleaning may be unsuited to premises distant from a driveway or road, and hoses may need to pass through windows to reach upper floors of a building. Hoses needed for truck mount and professional portable carpet cleaning may present an inconvenience or tripping hazard to users of hallways, and pets or children can escape through doors that must be left ajar for hoses. Heated or air conditioned air will also escape from buildings when doors are left open for hoses, potentially creating a significant waste of energy. Truck mounted carpet cleaning equipment minimizes noise in the room being cleaned, but may cause noise and air pollution offensive to neighbors, and may violate anti-idling bylaws in some jurisdictions. However, truck-mounted cleaning is much faster than portable equipment, and the extra heat will dissolve more spots and stains, and more vacuum suction power will reduce drying times.

A common process of hot water extraction begins with preconditioning. Alkaline agents such as ammonia solution for synthetic carpets, or acidic solution (such as vinegar solution) for woollen carpets, are sprayed into the carpet, then agitated with a grooming brush or an automatic scrubbing machine. Next, a pressurized manual or automatic cleaning tool (known as a wand) passes over the surface to rinse out all pre-conditioner, residue, and particulates. If an alkaline detergent is used on a woollen carpet, use of a mild acetic acid solution will restore neutral fiber pH. The acidic rinse thus neutralizes the alkaline residues, and can contribute to softening cleaned fabrics.

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Wikipedia