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Wednesday, November 25, 2015


I have spots on my carpet that disappear when cleaned, but gradually come back over a two week period. How can I stop it?


Answer #1:
This is a common occurrence called wicking. One of the worst offenders is ice melt compound (calcium chloride). During the carpet cleaning using wet methods, the soils deeper in the pile are loosened and, as the carpet dries to the air, they move along with the moisture to the tips of the fibers. If the material is sticky it will attract soils that show up as spots after exposure to foot traffic. Or, the soils themselves may just be darker than the carpetís color.
Since this is due to incomplete soil removal, the answer to your question is, rinse more thoroughly after shampooing. Or, you can touch up the spots with a bonnet (or encapsulation) which will remove the obvious soiling at the fiber tips and yet not put enough moisture into the fibers to cause the process of wicking to be repeated.
Lynn E. Krafft. ICAN/ATEX Associate Editor

Answer #2:
Reoccurring spots crop up when moisture activates residue concealed at the base of the carpet. Wet cleaning, and sometimes low moisture cleaning, produces capillary action. Excessive and/or dormant spills are then drawn to the surface. If your carpet warranty allows, bonnet cleaning with an encapsulation cleaner immediately following extraction will normally correct the problem. Or, bonnet clean a few days following cleaning. Low moisture cleaning prevents much of the wick-back. However, the spill is still residing untouched on the backside of the carpet.
About 30-years ago, I was shocked to observe the results after cleaning a carpet at a car dealership. It actually looked worse on Monday morning. Apparently all the grease tracked in had been spot cleaned by the employees using copious amounts of cleaner. The grease spills were no longer visible. But, sufficient residue was lurking at the base of the carpet or even on the backside, waiting to resurface.
Another corrective treatment requires placing a white towel over the spot immediately after cleaning. Then, place a weight (20-30 lbs.) on top of the towel and leave 24-48 hours. To absorb spots reoccurring at a later time - apply an encapsulation cleaner, blot with towel, reapply cleaner and then place towel and weight overnight. One thing about reoccurring spots: they are correctable. Donít give up; even a big-gulp is removable.
Gary Clipperton
National Pro Clean Corp.
(719) 598-5112

Answer #3:
Based on your description that the spots gradually come back over a two week period, I suspect the problem is that residue from the spot cleaner(s) you are using is attracting soil. I'd recommend two things:
1. Make sure the spotter you use is free-rinsing and doesn't cause rapid resoiling. To find a list of spotters that have been independently tested and approved go to , click on the link to the Seal of Approval program, and click on the list of approved spot removal products. Any of the products on the list will be safe, effective, and
won't cause resoiling.
2. Whenever possible, when cleaning carpet or doing spot removal, your last step should be to rinse with clear water or a non-detergent rinsing agent.
John Downey