Before having a carpet cleaned, you may find it helpful to understand some of the carpet cleaning methods. The best method for cleaning a particular carpet is dependent on a range of factors. All carpet cleaning methods offer various advantages, but also have some limitations. No single method is superior to all others. Properly performed under appropriate conditions, each method can provide satisfactory results. Often several methods can be combined to achieve the desired results. The following are some of the more prevalent carpet cleaning methods. Let’s start with the oldest form of modern carpet cleaning first:
In this method, detergent solution is released onto the carpet through openings in a rotary pad, whose rotary action converts the solution into foam and works it into the carpet. This method has very good agitation and is best suited for low pile commercial carpet or low cut pile carpet that is highly soiled. This method, unless it is used with some other type of carpet cleaning, has no extraction in the cleaning process but rather relies on vacuuming after the shampoo dries.
HOT WATER EXTRACTION
This is also referred to as ‘steam cleaning’. In this method, hot cleaning solution is sprayed under pressure onto the carpet and is then extracted with a vacuum source. The dirty solution is collected in a recovery tank and is usually poured into the sanitary waste system. The advantage of this sytem is that it has the ability to flush out large amounts of soil and contaminants in carpet. It is the most preferred method by all of the major fiber producers, such as DuPont, Monsanto and Allied Signal, as well as the carpet manufacturers like, Shaw, Mohawk, World and Queen. Because this method removes more contaminants than the other carpet cleaning methods, hot water extraction is favored by the Environmental Protection Agency (EPA) and is the preferred method of the Institute of Inspection, Cleaning and Restoration Certification (IICRC). Most higher quality carpets that have extended appearance and texture retention warranties require this type of cleaning every 12 months to 18 months in order to retain the warranty coverage. Factors that also affect the results of this method are: Operator Skill, Solution Temperature, Spray Pressure, Vacuum Power & Pre-spray: spraying solution some time before extracting. Ask for our “Comparison Sheet”.
NOT ALL HOT WATER EXTRACTION MACHINES ARE EQUAL
These machines are fine for spills and maintenance of lightly soiled traffic areas. But they lack the power needed to do the deep cleaning required to get out the grit that lies deep in your carpet pile and to maintain carpet manufacturer warranties.
These machines are many times more powerful than residential units. The number and size of vacuum motors and pumps plus heat exchangers differentiates one from another in terms of performance. The most powerful machines may have two power cords to enable household circuits to cope. A really good job can be done with these units if the operator has excellent training and takes his or her time. Sometimes portables are the only way the carpets in some locations can be cleaned.
Truck Mounted Units
These machines have large independent engines or run off the motor of the cleaning van. They can develop up to 1,000 pounds of pressure (though normally carpet is cleaned at only 500 pounds of pressure). They also heat the water to 180 or more degrees and have very powerful vacuums. These machines are expensive but they can leave the carpets drier in many cases when used properly. Typically, this type of hot water extraction machine should give improved results as well as decrease time on the job. Again, a really good job can be done with these units if the operator has excellent training and does the job properly.
Other Cleaning Methods
BONNET CLEANING (DRY CLEANING)
This is another method similar to ‘Shampoo’. Bonnet cleaning employs an absorben pad (‘bonnet’) attached to the bottom of a rotary machine. Detergent solution is sprayed onto the carpet and the rotary pad is used to agitate and remove the soil suspended in the solution from the carpet. Once one side of the pad gets soiled, the sides can be reversed. And when both sides get soiled, the pad can be replaced and later cleaned. This method has the advantage of drying very quickly because of the small amount of moisture used. It generally does a good job of cleaning the top 1/3 of the carpet pile that is visible to the eye. But does little to remove the heavier grit and sand that damages carpet over time. Because there is no flushing action or extraction, there is very little deep cleaning. This method may be considered as an interim cleaning between more effective deep cleanings. TIP: This method is used in the regular maintenance of commercial buildings.
DRY FOAM CLEANING
This method is very similar to shampooing in that it relies on the aggressiveness of the brushing action, which is usually counter rotating cylindrical brushes. The difference is that the solution is whipped into a foam and applied right before the brushes instead of a liquid as in shampooing. This does allow for faster drying times. Once dry, the residue containing suspended soil is simply vacuumed away. TIP: Some foams may leave a residue that is difficult to remove and may cause problems with subsequent wet cleaning.
This type of cleaning is ideal for specialized cleaning of loose or valuable rugs. TIP: In-plant cleaning is more expensive but you can save money by at least delivering and picking up the rugs yourself!