Steam Cleaning or Hot Water Extraction is the process where a cleaner is applied to the carpet, allowed to dwell and then extracted with either a clear water rinse or a rinse solution. This article will explain the process in greater detail.
Their are 2 different types of machines used for this process. Their are portable extractors and truck mounted extractors. Both of these systems will allow a dedicated operator to do a good job but we will explain both.
Portable extractors will contain 1 to 3 electric vacuum motors and a water pump which will generally be capable of water pressure in the range of 100 to 500 pounds per square inch. Some will be heated and others may require the operator to use hot water from the customers faucet.
Truck mounted extractors will usually contain 1 large vacuum motor capable of much higher vacuum levels than portable extractors and are capable of operating at 1000 pounds per square inch of pressure although that high of pressure would not be recommended and is seldom used. They will also have either a heat exchanger system which heats the water from the engines heat or a gas/fuel burner which heats the solution.
Both of these systems can be successfully used to clean your carpet but truck mounted equipment does have some advantages. It allows the operator to leave the machine in the van so that the machine is not venting inside the home. It provides higher vacuum and higher heat levels resulting in carpets that generally dry quicker.
In the steam cleaning process, a solution is first applied to the carpet. This pre-spray is generally allowed to dwell for 10 to 15 minutes before being extracted. The pre-sprays used vary greatly but most will contain a solvent of some sort to break up oily residue and an emulsifier to absorb and hold the soil until it is extracted. The solution should have a PH of no greater than 10 when it is used on stain resistant carpet to avoid damaging the stain resistance properties.
After the solution is given sufficient time to dwell, it is extracted with a carpet wand which sprays either clear water or a rinse solution and then immediately vacuums it back up. Some cleaners may also use rotary tools for the extraction. This is commonly referred to as rotary Jet Extraction and it is basically a spinning floor machine which has multiple vacuum slots and water jets. These machines allow the operator to make a greater amount of cleaning passes than traditional floor wands.
After the extraction step, the carpet should be raked. Raking the carpet lifts and separates the individual carpet tufts and helps restore the appearance of the carpet. It also aids in the drying of the carpet and removes any lines that were created from the carpet wand or rotary tool. If protection is being applied to the carpet, it should be applied before this step so that the raking will help distribute the protector evenly.
This process usually leaves the carpet dry within 4 to 6 hours. Some steam cleaners will be able to dry the carpet in as little as 1 to 2 hours through the use of carpet fans or extra drying passes with the machine. Some carpets will take longer to dry and should be dry within 24 hours. To speed drying, leave ceiling fans on and turn your fan to the on position on your thermostat. The main thing is to keep air moving through your home.