Hot Water Extraction

The Hot Water Extraction carpet cleaning method

hot water extraction carpet cleaning
What is the Hot Water Extraction carpet cleaning method?

Hot water extraction is a procedure for cleaning carpets whereby a carpet cleaning machine is used to remove dirt and soil from the carpet fibers. This type of cleaning system will also remove many types of stains. Firstly a pre-spray is applied to the carpet to dissolve dirt and stains. Then the carpet is agitated by using a brush or CRB machine. The hot water extraction system is then used along with a carpet wand consisting of spray jets and a vacuum slot. The machine consists of a high pressure pump to spray water onto the carpet from the jets and at least one vacuum motor to simultaneously remove the water along with the soil and dirt into the vacuum slot in the wand. There are many variations or types of carpet cleaning machines available on the market today, starting from low powered DIY machines such as Rug Doctor, more powerful portable extraction machines and also Truck Mounted carpet cleaning machines powered by petrol or diesel fuel.


carpet cleaning machine
Lets have a look at a typical carpet cleaning set up

Opposite is a portable hot water extraction machine which consists of a twin vacuum machine with a 600 psi pump. These machine usually stand outside the property to minimize noise and disruption inside the house if domestic cleaning is being carried out. The machine has a solution tank which is filled with water. A long vacuum hose and solution hose is used to reach into the property. 


vacuum motors hot water extraction
Vacuum motors

An essential part of the hot water extraction process is the ability to remove the dirt and soil from the carpet. The more powerful the vacuum motors, the better the airflow and the more successful and efficient will be the removal of dirt from the carpet. Either 2 or 3 of these motors are usually used in most portable carpet cleaning machines these days.


carpet cleaning pump
Hot water extraction pump

The image opposite shows the solution pump which sends the water down the hose into the wand. The more powerful the solution pump, the more efficient the removal of the dirt and soil from the carpet will be. Typically the water pressure of these pumps will range from 135 psi to 800 psi in most portable extraction machines.

High pressure pumps such as 800 psi can also be used for cleaning and removing slurry from floors if the company carries out floor cleaning.


Carpet wand

The carpet wand consists of a vacuum tube, a solution hose, water jets and a trigger valve to control the water flow.

extraction carpet wand
The carpet wand head

As can be seen in the photo, there are 2 solution jets that spray water onto the carpet under pressure. The vacuum slot recovers the water from the carpet and up the tube into the hot water extraction machine.

carpet wand jets and vacuum

Carpet agitation.

This is a typical carpet agitation brush. An essential part of the carpet cleaning process is carpet agitation. Once the carpet traffic spray has been applied to the carpet it will be necessary to agitate the carpet to work the pre-spray into the carpet. This will also loosen dirt and can also remove hair and fluff that is sticking to the carpet fibers.

carpet agitation brush
Using a carpet agitation machine or CRB.

A carpet agitation machine or contra-rotating brush (CRB) machine can also be used to scrub the carpet and work the pre-spray into the carpet. This method is extremely good at improving the results on heavily soiled or difficult to clean carpets. This type of machine uses two brushes rotating in different directions. The brushes supplied are usually soft, medium and hard stiffness depending on the type of carpet to be cleaned. It is extremely efficient at removing grit, soil, hair, dust and fluff from the carpet fibers before hot water extraction is carried out.

The CRB machine is also used for the dry cleaning or low moisture cleaning of carpets.

Carpet agitation machine CRB

Using hot water extraction for upholstery cleaning

Hot water extraction is also used for the cleaning of upholstery. The method is just the same only using specialist upholstery cleaning tools. There are many different types and sizes of upholstery cleaning tools on the market.

upholstery cleaning using hot water extraction method
The upholstery cleaning method using hot water extraction.

This is a typical 4 inch wide upholstery cleaning tool. As can be seen in the photo and similar to the carpet cleaning wand, there is a spray jet, a vacuum slot and a trigger valve to control the water. In this type of tool the spray area is enclosed to prevent over spray. Much lower water pressures are used, typically between 50 and 150 psi depending on the size of the spray jet and the material being cleaned.

upholstery cleaning tool hot water extraction

Check the video below to see how carpets are cleaned using the hot water extraction method.

The video blow shows how hot water extraction is used to clean upholstery.