Hot-water extractors may be the popular choice today, but cold-water alternatives are causing many BSCs and in-house service providers to second-guess their selections.
The good news about cold water — and the bad news for hot — comes down to the ability to clean all carpets safely.
“Hot water has been known to shrink carpets,” says Glenn Rothstein, president of Bio-Shine Inc. in Spotswood, N.J.
For example, wool carpets, which might be in high-end office complexes, are especially prone to shrinkage. In addition, hot water is more likely to fade dyes. With cold water, these issues are mitigated or nonexistent.
Proponents of cold-water extractors acknowledge that hot water does clean better than cold — but only by itself. When using chemicals, cold works as well, if not better.
“If you were going to attack dirt with hot water with no chemical and cold water with no chemical, hot water cleans better,” says Rothstein. “But that’s an age-old look at things. You’ve got to realize, the chemicals today are so much better, you really don’t have that need.”
Dan Dillon, owner of CleanItSupply.com and Clean It Janitorial Services, Norristown, Pa., agrees. When using chemicals, hot water has no advantages over cold as long as the operator conducts proper stain analysis and pre-treatments, he says.
“Cold can perform just as well as hot water as long as the chemistry is in place,” he says. “The most important thing is educating people who perform carpet cleaning — if they understand the entire process of cleaning with alkalines, rinsing with acids, and doing the complete system, they will get the same result as the guy with hot water extractor.”
In addition, certain stains are more easily lifted with cold water.
“Cold is better on protein stains like blood, milk or eggs,” says Jennifer Wagner, president of Masco Industrial Supply in Springfield, Ill.
Hot water, on the other hand, may set stains.
There is one scenario, however, that hot water is definitely preferred: removing excess solution. If previous operators used too much chemical solution on a carpet, the chemical residue will attract dirt from people’s shoes when they walk on it, creating dirty tracks in heavily-trafficked areas. The best way to remove the excess is with hot water.
For some users, the question of choosing hot-water extractors or cold-water machines comes down to dollars and cents. Cold-water equipment can save money for cleaning companies and departments, as well as the facilities they clean.
Portable hot water extractors with internal heaters run $500 to $1,000 more per unit than cleaners with no heater, Dillon says. When buying multiple machines that can really add up.