ICS Magazine

Low-Moisture Carpet Cleaning: The Basics

April 2, 2012

Have you ever been frustrated with a particularly tough cleaning job and screamed (preferably in your head so your customer didn't hear you), "I'm through with hot-water extraction - it's too hard for these lousy results!?"

Have you ever been frustrated with a particularly tough cleaning job and screamed (preferably in your head so your customer didn’t hear you), “I’m through with hot-water extraction - it’s too hard for these lousy results!?” 

While we may have all been tempted to shout this based on a few jobs over time, the vast majority of properly cleaned carpet using the hot-water extraction method turns out very well. Without a doubt, it is the preferred method of a majority of professional carpet cleaners. But with that said, where does low-moisture/encapsulation cleaning come into the picture?

As you may know, most of my articles deal with the tools (i.e., gadgets) of our trade and today I plan to review some of the equipment used in low-moisture cleaning. But in addition, I’ll review some of the methods that this equipment employs. I have also asked some experienced cleaners, instructors and manufacturers to pipe in. I would like to thank them for their contribution.

Rick Gelinas, a professional cleaner and supplier to the industry states, “Hot-water extraction is still the most effective way to flush the greatest quantity of soil from the carpet in a single cleaning. However, for regular maintenance of a commercial carpet, hot-water extraction also has some limitations.” Rick then listed what he believes are the seven key benefits of encapsulation cleaning:

1. Common wicking issues and recurring spill stains can be eliminated.

2. Dingy looking carpets can easily be transformed to a like-new appearance.

3. Carpets stay clean longer between cleanings.

4. High production and low end-use cost.

5. Simple cleaning process that’s easy to train on.

6. Lower impact on the environment than traditional hot-water extraction.

7. Quick dry times (normally two hours or less).

So where exactly does low-moisture cleaning enter the picture? I asked Jared Twitchell, brand manager for Bridgepoint Systems. “For some customers, low-moisture cleaning is not an option - it’s essential,” he says. “For 24-hour operations like hospitals, casinos and airports, carpet must be useable immediately. For jobs such as these, the commercial carpet cleaner needs to understand and have encapsulation as one of the services he offers. Without the ability to offer this, he is passing up on business that another cleaner will get because he understands his customer’s needs better.”

Let’s take a brief look at the basic equipment used in low-moisture/encapsulation cleaning:

Counter-Rotating Brush Machine

There are several different brands of this equipment available. Featuring two brushes that turn in opposite directions, it moves easily over the any kind of carpet. Different stiffness of brushes can be used depending on the severity of soil and type of carpet being cleaned. 

Dane Gregory, an industry expert and instructor in commercial cleaning, explains the reasons he prefers this machine: “The benefits of our counter-rotating brush machine are the options it offers for carpet maintenance. Option one is the fact it can act as a junior varsity pile-lifter, removing dry soils much better than just vacuuming alone. Since the brushing action gets below the carpet surface, it has the ability to get much lower into the carpet than vacuuming alone. It is equipped with catch trays that actually pick up an amazing amount of soils.”

So what about the other options for carpet maintenance?

“Option two is the idea that it leaves the carpet in a more upright position to help the carpet look more uniform in appearance,” Gregory continues. “Because of the cylindrical brush action, the carpet tufts are separated by the brushing action, looking more full and upright. Low spots in the pile are often mistaken for soiled conditions.” Gregory says option three is that the machine is a “great tool for agitating low-moisture encapsulating products. Higher productivity rates than other interim maintenance methods mean more potential profit for carpet cleaning companies.”

Single-Disk Rotary Machine

This type of machine has been in use for many years. First used for scrubbing hard floors, it was adapted to be used for carpet scrubbing or shampooing, and was the primary method of carpet and rug cleaning until hot-water extraction was invented in the late 60’s and early 70’s. It can be used with a brush, a fiber pad, or a bonnet and operated with a built-on tank to disperse solution through the brush or pad. Many professionals prefer to spray the solution on in advance with a pump or electric sprayer and then work the solution with the machine.

George Rimel, the owner of a company that does very low-moisture (VLM) commercial cleaning states that the typical 175 rpm rotary machine, while not his favorite, is, “the cheapest way to start VLM cleaning.” He continues, “Use either a carpet brush head or standard VCT pad driver and you are ready to go.”

OP/Oscillating Pad

This type of machine may have a round or a square drive plate that powers a brush, fabric-type bonnet or synthetic fiber pad. It is preferred by some professionals for its complete agitation, as it works all sides of the carpet fiber. And when used with a bonnet, some extraction of the soil is taking place. 

As John Geurkink, a manufacturer of OP machines, notes, there have been improvements made in just the past few years that increase the speed of oscillations.

“We found that we could utilize properties of the encapsulation products that seemed to be unattainable in the past,” he says. “The level of clean went way up, the binding of residues and soil on the carpet into vacuum-able substance, basically adding it to the particulate soils ready for vacuum removal, allowed us to clean carpets and keep them clean well beyond what we had seen in the past. We did all this while increasing the speed of OP cleaning to a level where the operator realized incredible profits.”

While considering the use of a rotary or OP machine combined with a bonnet, you might want to consider what Shaw Industries states in their carpet maintenance guide: “It is not a substitute for hot-water extraction. It has very limited capability for soil removal and often leaves most of the detergent in the pile. The spinning bonnet may distort the pile of cut-pile carpets and leave distinct swirl marks. Shaw’s experience has been that more customer soiling complaints result from this system than all other causes combined. In addition, the bonnet system may damage the edges of some carpet tiles.”

As Shaw stated, I believe a bonnet cleaning system can be damaging to certain carpets when misused. At the same time, I believe a professional cleaner would be ill-equipped if he wasn’t able to perform using this system. If used on commercial loop pile with proper encapsulating chemistry, it can be quite effective.

A few months ago, I had an opportunity to try a hybrid low-moisture cleaning system. A professional carpet cleaner invited me to a commercial job that had previously given him problems. The carpet was an abused dense low pile commercial glue down. On the previous restoration cleaning he had extracted it, but it had so much impacted soil that wick-back was a problem. On this cleaning, we decided to apply the following low-moisture hybrid system. Here’s what we did:

  • We pre-sprayed with an aggressive, high pH solution. We put just enough on to wet the top two-thirds of the carpet.
  • We ran over it with a counter-rotating brush for extra agitation.
  • We did a single pass drag wand extraction. The trigger is only held on for one extraction pass. This is to keep the solution in the top two-thirds of the carpet and out of the backing where the soil is condensed.
  • We then sprayed an encapsulating protector/anti-wicking solution again, only wetting the top two-thirds of the carpet. 
  • We followed with a dry bonnet attached to a rotary machine. We worked with cotton and microfiber bonnets and both seemed to function equally well.

Did we get all the dirt out of this carpet? No! (Frankly, removing all the soil from this carpet was impossible.) But did the carpet look good? The business owner was very impressed and so was I. And it stayed clean much better than any of the previous cleanings.

Triple Head Planetary Rotating Machine

This machine has three small brushes that rotate independently as the larger driver plate rotates in a different direction. Through this action, it is better able to clean on all sides of the carpet fibers. It offers high production speeds and does not have the torque problems associated with a single-disc rotary machine. The machine comes with a large tank that feeds solution down through the brushes or fiber pads, creating a light foam. I first saw this machine 30-plus years ago when Ed York introduced it to bunch of rookie carpet cleaners. It did a good job of cleaning then and is even better now when combined with modern encapsulation chemistry.

Professional Testing Laboratory in Dalton, GA has shown that this carpet cleaning machine, along with high-quality encapsulation carpet cleaning products, fiber pads and making 22 passes on a commercial cut pile carpet, will not damage the carpet.

This gives you an idea of the machines and processes used in VLM/encapsulation cleaning. It is by no means exclusive, as there are other methods and equipment that may be used. As with any process involving people, an essential principle in effective safe cleaning is to have a well-trained consciences professional performing the work.

Let’s finish with some thoughts from Scott Warrington, technical service manager of Interlink Supply: “Low-moisture cleaning has been around for 50 years, since the days of Glory foam rug cleaner. It has become really important in commercial carpet cleaning with the convergence of two things: Equipment that provides high production rates, allowing cleaners to bid competitively, and secondly, advances in encapsulation chemistry that result in great looking carpet when the job is done.”