How Pressure Washers Get Things Clean

How Pressure Washers Get Things Clean

When using water, soap, and other cleaning solutions are not enough to remove tough stains, it’s time to bring out the pressure washer. Just blast things with a pressurized water jet and you will see your outdoor patio cleaner than ever.

Whatever color your car, deck, siding, or furniture is, you are sure to see them looking brand new with the help of a pressure washer. There are a variety of applications you can try, but before you try them all, take a closer look at how a pressure washer works.

The science behind pressure washers

Many people already know that water works great for removing almost anything. This is because water has molecules that have electrical polarity, making them stick to things. By adding detergent, the cleaning power of water becomes greater.

The combination can now break down and flush away stains and grease. But when it comes to stubborn dirt that does not come off, even with scrubbing and scouring, more pressure is needed.

A pressure washer is engineered to make cleaning faster and easier, especially in this kind of situation. It uses a narrow nozzle to blast a jet of hot or cold water on the surface to remove the dirt.

As the water travels fast through the nozzle, the kinetic energy increases, which makes it more effective in getting rid of dirt on the surface. Since it is only water, it does not cause damage to hard surfaces; however, it is still recommended to test the pressure washer to ensure that it won’t harm what you are trying to clean.

Different parts of a pressure washer

A pressure washer might look like a complicated machine, but in reality, it’s just a simple water pump powered by either an electric motor or gas. It’s like an ordinary faucet that squirts water from a hose.

You can control the pressure by rotating the lever or using the trigger gun. To further understand how a pressure washer works, you need to understand its main parts and uses.

Water inlet

The water inlet serves as the hose connecting the pressure washer to the water supply. Most of the models today include a filter in the inlet so that there will be no dirt and debris clogging your pressure washer. Though grit is small, it can damage the surface of what you are cleaning if they blast out of the nozzle at high speed.

Electric motor or gas engine

The main role of the motor or gas engine is to provide power to the water pump. The electric pressure washer needs electricity and therefore, has to be always near an outlet. On the other hand, the gas engine needs fuel in order to function.

Water pump

The water pump is probably the most important part of a pressure washer. It is responsible for sucking the water and detergent from the supply or faucet and pushing it the other way to squirt out water or hot soapy water in a high-pressure jet. Water pumps can handle a water flow ranging from 1-2 gallons per minute.

High-pressure hose

Pressure washers use a high-pressure hose because it can handle the amount of water and the pressure flowing through it, unlike an ordinary hose or tubing. The high-pressure hose is made of wire mesh and two layers of high-density plastic.

Take note that the safety level of high-pressure hoses should be 300% greater than your washer. For example, a 2000-PSI pressure washer should have a hose that can withstand at least 6000 PSI.

Cleaning attachment

The cleaning attachment for your pressure washer depends on your preference. You can get a trigger gun that lets water through by squeezing the handle. Or you can opt for a rotating brush and a spinning wand spray, too.


The electric pressure washer has residual current devices (RCD) which are designed for your protection should there be an electrical fault.


This is how a pressure washer works, in simple terms. The detergent and water flow in through separate hoses. With the electric motor or gas engine power, the water pump draws in and mixes the water and detergent together. Some washers heat the water up to 70° Celsius for a better cleaning effect.

After this process, the water pump then releases hot, soapy water through the high-pressure hose and cleaning attachment. The nozzle is designed to set the pressure higher or lower.