Advantages of Hot Water Pressure Washers

Cleaning with hot water: Pressure washers clean even better at a constant pressure. Alongside improved results and faster cleaning and drying times, hot water pressure washers also have a measurable germ-reducing effect. When the steam stage is used, even delicate surfaces can be gently cleaned with temperatures of up to 311°F. Furthermore, the machines allow for a reduction in the working pressure, the time required, and the volume of cleaning detergent that is used. This means that cleaning with hot water offers a number of advantages and various possibilities for optimizing the cleaning process.

A worker uses a Kärcher hot water pressure washer to clean under benches at the Red Rocks Amphitheater

Even More Efficient with Hot Water

Commercial pressure washers are a staple when it comes to efficient cleaning and cleanliness. Compared with methods without pressure, they are characterized by low water consumption and high cleaning power. Hot water pressure washers offer even more benefits, as they generate hot water up to 185°F and tackle stubborn dirt even faster and more effectively. For commercial users, the combination of hot water and high pressure offers greater cost-effectiveness, in addition to clear advantages such as shorter drying times and a reduced need – or even no need at all – for cleaning detergents.

A worker cleans construction equipment with a Kärcher hot water pressure washer

Overview of Advantages of Hot Water Pressure Washers

  • More effective breaking up of lubricant residues
  • Shorter cleaning times and labor cost savings
  • Germ-reducing effect and virus inactivation
  • Shorter drying time
  • Significantly reduced use of cleaning detergents
  • Protection of delicate surfaces and the same cleaning effect at a lower working pressure

Numerous Advantages: Faster and More Efficient Cleaning with Hot Water Pressure Washers

Close-up photo of a pressure washer cleaning a car engine with a Kärcher hot water pressure washer

The use of hot water pressure washers accelerates the cleaning time by up to 40 percent compared with cold water machines  – thanks in part to the faster drying process for the clean surfaces.

Heat energy is an essential factor that influences and accelerates cleaning processes. It is not without reason that temperature – along with mechanics, cleaning detergent and time – is one of the four parameters that mutually impact each other and that, according to Sinner's circle (effect mechanism for describing cleaning sequences), impact the success of a cleaning process.

The addition of heat means that dirt and lubricant residues are broken down more quickly. Each increase in temperature by 50 °F accelerates the chemical processes and halves the reaction time. Oils, fats and soot dissolve due to the addition of heat and can then be removed more easily. The emulsifying of oils and greases is also accelerated in warm water.

Various practical applications, from workshops and handicraft businesses to large industrial enterprises, show that the use of hot water can reduce overall cleaning time by up to 40 percent. This means that labor costs are reduced.

Another significant factor in the use of hot water pressure washers is the faster drying time. Surfaces that are cleaned using hot water, rather than cold, remain slightly heated and therefore usually dry faster.

While conventional cold water machines only achieve the desired result with the right cleaning detergent, hot water machines get to work more quickly. Because stubborn dirt – including encrusted grease, resin or oil residues – usually dissolves in hot water, significantly less cleaning detergent is required. In some cases, the use of detergents may not be needed due to the effectiveness of the hot water. This protects not only the environment, but the user's wallet as well.

Hot water pressure washers are also especially suitable in areas where maximum hygiene is required and micro-organisms and contamination are targeted during cleaning. This applies not only in the food sector – from artisan butchers to large-scale industrial production – but also in agriculture, where it is essential to pay attention to cleanliness in young animal husbandry and milking parlors.

Thanks to the combination of high pressure and hot water at a temperature of up to 185°F, a substantial reduction of contamination is achieved. This germ reduction is often sufficient without the use of disinfectants in order to actual hygiene requirements. Compared to the use of cold water, hot water cleaning does not lower the base temperature in the room. This is not insignificant in agriculture, for example when newly housing young cattle, and it is vital for chicks, as they are particularly sensitive to temperatures that are too low.

Hot water pressure washers can be used to perform highly demanding cleaning tasks that cannot be accomplished with water, cleaning detergent, and hand scrubbers alone. With steam at temperatures up to 311°F, the steam stage allows even the most stubborn dirt to be loosened – gently and usually without detergents. This method is best suited for the gentle cleaning of delicate surfaces, as full cleaning power can be achieved at a considerably lower working pressure and with a reduced water volume. The steam stage is highly environmentally friendly and is particularly well-suited to removing bituminous coatings, paint, soot deposits, lichen, and algae. Reduced water consumption also means less waste water.

The most significant advantage of hot water pressure washers is their increased cost-effectiveness. This is especially true for regular commercial use. The longer and more often the machine is used, the more significant the cost advantage becomes. Although the purchase price for a hot water pressure washers is often over twice that of a cold water machine with comparable pressure and capacity, the machine quickly pays for itself through lower labor and operating costs.

The reason for the higher purchase price is its more complex technology, in particular the burner. Higher energy consumption, as a result of the heating system, must also be taken into account in the maintenance costs. However, these two expenditures are quickly offset by the high potential savings offered by hot water machines. This begins with maintenance costs, where the cost of heating energy is quickly offset by the large volumes of water and cleaning detergent saved. A key factor in profitability calculations is that cleaning times can be up to 40 percent shorter using hot water. This is reflected in the labor costs, which, over the entire lifetime of a commercially used hot water pressure washer, are many times higher than the purchase and operating costs.

Using hot water pressure washers, it is possible to eliminate weeds sustainably. The principle of thermal weed control is a much gentler process for the environment and for surfaces; it is based on a basic biochemical rule – most proteins denature at a temperature of around 107°F. This means that the proteins change, break up, and are no longer able to fulfill their functions. The heat required for this can also be generated using hot water pressure washers. Weed removal using hot water is the only chemical-free method that also reaches the roots.

How Hot Water Pressure Washers Work

Hot water pressure washers can increase the water temperature from approx. 53°F to up to 311°F in the steam stage. The water in hot water pressure washers is brought up to temperature in a burner boiler with a double-helix heating coil, which features a compact design and high heating output. The low-emission burner can be operated using regular biodiesel. Optionally, there are also machines with an electric boiler. These are used where the space must be completely free from exhaust fumes – for example in large kitchens, swimming pools, or other enclosed spaces. At full capacity and maximum working pressure, the pressurized water is heated to max. 185°F. By reducing the water volume, hot steam can be generated in the heating coil at temperatures up to 311°F; this activates the steam stage, which is particularly intensive and gentle on surfaces.


Hot Water Pressure Washers for Cleaning and Disinfecting Large Areas

Intensive and meticulous cleaning with hot water pressure washers makes it possible to achieve high standards of hygiene. They can not only be used to reach places that are difficult to access manually, such as crevices and cracks. They are also particularly useful for cleaning and disinfecting large areas such as ceilings, walls and floors, and are effective at combating germs, bacteria and viruses.

The use of cleaning detergents and disinfectants plays an important role in cleaning processes. But what many people do not know is that hot water also makes a significant contribution to fighting disease-carrying germs. When using hot water pressure washers, the water temperature has a significant effect on the reduction of germs, as well as viral and bacterial colonies. Thanks to the combination of high pressure and the hot water at a temperature of up to 185°F, a substantial reduction of contamination is achieved. This germ reduction is often sufficient without the use of disinfectants in order to satisfy hygiene requirements. To further improve its cleaning effectiveness, the addition of disinfectant by the hot water pressure washer is recommended.

A worker uses a Kärche hot water pressure washer to clean and disinfect a commercial kitchen

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