Wednesday, February 20, 2013
how long will it take for my carpets to dry?
After spending time, effort and expertise getting a carpet completely clean, most customers ask the inevitable:
"How long will it take to dry?"
Some ask the question because of previous bad experiences.
It’s been known to happen: A carpet is professionally cleaned and it takes a day — or even two — to completely dry.
That’s a time frame unacceptable in today’s world of modern carpet cleaning equipment and especially with the popularity of low moisture cleaning.
Any carpet still wet after 24 hours can be susceptible to microbial growth. That will only create trouble for your cleaning company.
The low moisture debate
When asked how long a carpet will take to dry, your answer will depend on many factors, such as the method of cleaning, the skill of the technician, how large the job is and what you do to help remove the moisture before you leave the job site.
The skill of the technician is important. It is possible to overwet a carpet using low moisture cleaning, this occurring mainly because of operator error.
Low moisture cleaning methods should — logically — take less time to dry, and may use no detectable moisture at all, such as with compound cleaning.
Low moisture — with a twist
Many cleaners today say that low moisture cleaning isn’t specifically about how much water is used in the process.
They say that low moisture cleaning can be performed with a truckmount or high performance portable; low moisture cleaning isn’t particularly the amount of moisture applied to the fiber, but could be identified as the measurement of moisture residue immediately after cleaning.
In other words, if you use a system that has a typical water flow greater than traditional low moisture methods, but has a recovery system that leaves the carpet fiber as dry as a traditional low moisture method, you are using low moisture cleaning.
Getting from wet to dry
You may notice that when you clean just one or two rooms in a home or commercial location, drying occurs rapidly — so rapidly that the carpet is dry to the touch by the time you store your equipment.
But when you clean several rooms, or the entire home or commercial location, odds are increased that residual moisture is higher than you expected, even though you followed the exact same protocol and used low moisture cleaning methods.
A physics point that comes into play is the fact that high pressure moves to low pressure in any given area — when it can — which means that if you don't create an atmosphere in your work area so moisture can move out, you won't have as much success in rapid drying.
As you clean a room, and you increase the grains or amount of moisture in the air, that moisture needs to be removed from the air so more moisture that you create in the carpet can evaporate.
If the air is saturated, you won't have effective evaporation. Air temperature, relative and specific humidity, dew point and vapor pressure all come into play when attempting to rapidly dry carpet during and after cleaning.
Steps you can take
As previously mentioned, using low moisture cleaning is an obvious step to take to accelerate drying, simply because there is less moisture used in the entire process.
There are several informative articles on www.cleanfax.com that illustrate modern low moisture cleaning methods. After opening the website, type “low moisture cleaning” in the search box.
Regardless of the method, some cleaners feel that if they simply create ventilation by opening doors or windows that they will effectively accelerate drying.
However, commercial facilities typically have no option of outside air transfer, and have to rely on the heating and air system and your own drying tools.
But if you are able to do a physical air exchange (opening doors/windows, etc) and the outside specific humidity is higher than indoors, exchanging the air by opening windows or doors will not lower dry times.
If the outside air is more conducive to drying (lower specific humidity), then it would be acceptable to exchange the air.
Otherwise, mechanical means such as the HVAC and air movers would be best.
As you finish an area, place the airmover in such a way as to create the most airflow, which will sweep moisture away from the air immediately above the carpet and allow more moisture to take its place.
This is called "Bernoulli's Principle" and basically means that airflow across a surface reduces air pressure, allowing moisture to move into that area.
Think of how airflow creates lift for airplanes. That same principle helps in the drying of carpet fibers.