Cleaning Filter Lines Out of Carpet


When carpet cleaning, it can be tough cleaning filter lines, out of carpet. These dark lines are also called “filtration soiling” They're along edges of walls, under closed doors, around edges of a couch, under draperies etc.

Super small particles of soil, carried by air, are directed under walls, doors, couch skirts, drapes and through staircase spaces. The carpet fiber becomes a filter, like the HVAC intake.


Misdirected air, in the home, can sometimes be caused by air intakes that are too small for the capacity of the HVAC unit. The cure can be as simple as adding another air supply line. Too much air being ducted out of the home by dryers, flues and exhaust fans can also contribute.


A big problem, with cleaning these lines out of carpet, is that many of the soil particles are smaller than the soap molecules. These very small soil particles penetrate deeply into the fiber structure. Some can be removed while others may never come out.


A Filter Line Cleaning Procedure:



Dry vacuum the lines, before starting. They may not “look” better after vacuuming but you will have removed some of the material, THE EASIER WAY. To prove it, place a white towel over the vacuum hose while you vacuum.


There is no one thing that works in all, filter line, situations. Experiment on each job. What worked on the last job, may not work here.


1.    Start with a neutral spotter, such as Bridgepoint Avenge. It sometimes works great.

2.    PRESPRAY WITH LOTS OF WATER, (stair tool) and agitate the water and Avenge mixture with the long,     angled handle, brush.

3.    The idea is to separate the microscopic particles from the fiber by a combination of chemical breakdown,       agitation and “flotation” or “suspension” in our solution.

4.    Extract with the vac hose or crevice tool. CONCENTRATED EXTRACTION can be a big part of separating     the filter line particles from the fiber.

5.    Wipe the baseboards; it can get sloppy.

6.    If more remains, add Citrus Spotter, to what is there already, and agitate.

7.    If more remains, add a high pH filtration solution to the mixture…..agitate.


Sometimes the stain is a combination of water and dry solvent base material and you’ll need both.


8.    Extract with vac hose or crevice tool. You want the most airflow you can get.

9.    Another option, if staining remains. RINSE OUT WHAT’S ALREADY THERE, apply  Urine Stain Remover,  (an oxidizer) allow dwell time and rinse.

10.  Extract.

11.  If black/grey is still visible, wipe with a white terry towel. The fiber to fiber agitation can remove some of the        soiling that the other methods didn’t get.


If the situation is bad enough, YOU MAY NOT GET IT ALL, particularly if candles have been burned, in the home.


The ancient secret ………..effort.


Charge accordingly.


                            MAKE MONEY!

                      Dennis Klager

                IICRC Instructor        


















Copyright 2012 by Dennis Klager