Cold Water Extraction: Is It Effective On Carpets?

In this article, industry manufacturers answer common questions asked by building service contractors. 

Is cold water extraction as effective as traditional hot water extraction?

This is one of the great debates of the carpet cleaning industry. Scientifically, hot water has been proven to improve the effectiveness of cleaning chemicals. However, many new carpet cleaning chemicals perform very well using cold water. 

Many green cleaning advocates encourage the use of cold water for two reasons:

1. When hot water and chemicals are mixed, they can release fumes that can be potentially dangerous to the user. Cold water minimizes this.

2. Cold-water machines generally use considerably less energy, making the machines much more sustainable, and very often these systems are more cost effective as well.

Our recommendation is to evaluate the soil load and make a determination from there whether to use a hot- or cold-water machine. For excessive soiling, hot water may prove more effective.

— Jolynn Kennedy, marketing director, Tornado Industries, West Chicago, Ill.

Cold water should never be used in a carpet extractor. It’s just not very effective. Most carpet extractors use hot tap water, which is about 120 degrees Fahrenheit. Cooler water than this would be less effective. Some carpet extractors have built-in heaters that will heat the water to higher temperatures. The hotter the water, the more effective the cleaning. Even when using a carpet extractor with a heater, it runs more efficiently if hot tap water is used to fill the tank.

— Scott Keller, vertical market manager–commercial buildings; Bob Abrams, product manager; and Brian Simmons, product manager, Clarke, Plymouth, Minn.

Is there a stair extraction tool available to clean the nose of stairs? If not, what kind of machine can easily clean stairs?

Effective wand cleaning is very dependent on the wand employed. Many new wands are designed to clean all areas of stairs thoroughly and effectively.

— Jolynn Kennedy, marketing director, Tornado Industries, West Chicago, Ill.

I have not seen a tool specifically for cleaning the nose of the stair.  Nevertheless, most hand tools will do this fairly effectively.

— Scott Keller, vertical market manager–commercial buildings, Bob Abrams, product manager, Brian Simmons, product manager, Clarke, Plymouth, Minn.

The EPA advises that carpets be dried within 48 hours to prevent mold and mildew. However, LEED recommends 24 hours. What are your thoughts? How fast should carpet be dried before mold and mildew become a problem?

As you point out, there has been much debate on this topic. In fact, the Low Moisture Carpet Cleaning Association takes this even further, suggesting carpets should dry within two hours to help prevent mold and mildew from developing. 

We believe carpets should dry as quickly as possible and suggest they dry in 24 hours or less.

A moisture-controlled carpet extractor can help ensure carpets dry in 24 hours or less, but cleaning professionals should know that many new wands have been developed using new “atomizing” technologies. These technologies apply and remove moisture so effectively that they can prove as effective — if not more effective — as using a low-moisture extractor.

— Jolynn Kennedy, marketing director, Tornado Industries, West Chicago, Ill.

I suspect that the EPA number is based on the science of how long it takes for mold or mildew to grow. Any good carpet extractor should be effective enough to allow a carpet to completely dry within 24 hours. However, in the event that high humidity and/or insufficient air movement in a room is prevent the carpet from drying rapidly, an air mover fan should be employed to reduce dry time.

— Scott Keller, vertical market manager–commercial buildings, Bob Abrams, product manager, Brian Simmons, product manager, Clarke, Plymouth, Minn.