How Does A Pressure Washer Work?

Pressure Washer Jet Washer Cleaning

Last updated on October 18th, 2022 | By: Grady Galvez

You might know that pressure washers get your cleaning jobs done faster, cleaner and that too with ease. It is a perfect tool for cleaning your patios, decks, driveways, your backyard patio furniture, vehicles or cleaning surfaces before a paint job. Literally, anything that is impossible to clean with your regular scrubbing and scouring with chemicals and soaps.

But do you know how a pressure washer works? How it gets everything clean so fast and what are the parts involved in cleaning process?

When you make up your mind to buy a pressure washer, it is really important to understand it’s working. Pressure washers are an expensive investment and it is really important to know its basic functioning to avoid any mishaps to machines and self.

Let’s read more of this!

Why Pressure Jets Get Things Cleaner?

Pressure jets use water as an integral part to clean. The water has mild electrical polarity. Wherein its one end is positively charged and the other negatively charged. This unique quality helps them to stick to things all by themselves.

The same scientific concept works for pressure jets. When we add pressure washer detergents or soap chemicals , its cleaning capacity increases many folds. Its breaks gauge and grease and water can easily flush this all away.

Pressure Washer Jet Washer Cleaning

For more stubborn stains and dirt, pressure washer comes to the rescue. The pressure washer uses high-pressure jets of water (hot or cold) which when passed through a narrow outlet, breaks even the toughest of dirt blocks. The working is simple – the water uses the kinetic energy given by the pressure washer to break the dust and dirt, it just works like a ramming hammer.

The best part of this is that as the main cleaning agent is water, it does no harm to the surface. But as a precautionary measure, it is always advisable to check the pressure washer on a testing area to make sure it is harmless. Plus it is always a smart step to read the manual and instruction before starting.

Parts of Pressure washer:

A pressure washer is a simple machine. The main function is to simply pump water with the help of an electric motor. It uses water from the tap and then uses pressure from the pressure washer to accelerate the water to very high speed through hose fitted with a trigger gun. To understand this better, let’s understand the various parts of the pressure washer:

Pressure washer Water Inlet

Water inlet: It is a hose that acts as a connector between the pressure washer and the main supply of water. It is fitted with a filter that stops the entry of dirt and external particles from entering the washer and blocking the machine. If this debris enters the washer it can damage the whole machine. It is also dangerous as pressure would catapult the debris out, which can harm humans or property.

Electric motor or gas engine: The smaller pressure washers are usually run on electric supply, but the bigger ones run on gasoline.

The power typically is around 3-5 kW/ 3.5-5.5 HP. The work which is located outside or off home locations like workshops require a gasoline engine.

Pressure washer Electric Motor Or Gas Engine

As these locations may have an electricity shortage or the cable can cause harm, so the gasoline engine is the best choice. This engine or motor powers the water pressure pump.

Pressure Washer Water Pump

Water Pump: It is the main component of the pressure pump. In design, it is similar to a manual groundwater pump. The only difference is that it is operated by electricity or gasoline instead of hands.

The working is simple, the pump due to the engine moves in one direction, it sucks water, and when the pump is moved the other way the water comes out at very high pressure. These washer pumps are designed to handle 1-2 gallons of water per minute.

High-pressure hose: This is the pipe that runs out from the washer to whatever cleaning connection you’ve chosen to utilize. A conventional piece of tubing wouldn’t have the option to endure the high-pressure of the water moving through it.

The high-pressure hose is strengthened with wirework and has at least two layers of high-thickness plastic. It’s critical to utilize a hose that has a higher pressure rating than the pump in your pressure washer.

High Pressure Washer Hose

However, if your washer accompanied your own hose, there shouldn’t be anything to stress over. Ordinarily, the security edge on pressure-washer hoses is around 300 percent, so if your washer is appraised at 2000 psi, your hose ought to have the option to withstand pressures of at any rate 6000 psi.

Pressure Washer Cleaning Attachment

Cleaning attachment: The cleaning attachments are really helpful apparatus in a pressure washer. There are different surfaces or places where you need to clean. Every surface requires a different cleaning attachment.

You can select from a simple trigger gun to a rotating brush which is useful to clean your drive. They also have extension wand spray and many more varying from model to model.

Power Washer Working - Things To Consider

The working of the electric pressure washer can be summarized as follows:

  • The process starts when the detergent or cleaning mixture first flows to the container through the hose.

  • Then Water flows through a filtered hose which is attached with the tap or faucet.

  • The washer starts with the help of an electric or diesel-powered engine.

  • The water pump or impeller then mixes water and detergent which is drawn in. They also heat the water to a temperature of 50-70 degrees.

  • In the final step, the water comes out in jet speed through hose and cleaning attachment. The speed is also increased due to the narrow nozzle at the end.

The benefit of the pressure washer is that it does work much more effectively than normal low-pressure pipe cleaning and that too in 80% less water. Which makes it an economically wise decision.

What's A Real Washer Like Inside?

Though it is highly technical and compiles to understand the whole internal structure of the pressure washer, it can be simplified for the general understanding. It contains the following structural parts:

  • One outer plastic covering.

  • One electric motor.

  • One insulated plastic foil, which ensures the waterproofing for the motor.

  • The central shaft in the motor which spins at high speed running the water pump.

  • One reciprocating water pump.

  • One pump piston.

  • One water pipe which sucks the water in and out.

Drawbacks of pressure washers:

Pressure washers are really handy and useful for household and commercial cleaning. But like every other good machine this also has some limitations or drawbacks:

  • The dirt is moved at high pressure, so dirt removed gets accumulated to different places.

  • Uses a lot of water, can go up to 2 gallons per minute.

  • Needs good drainage or can cause flooding.

  • Extremely noisy.

  • Can be very messy, as can cause a lot of filth in all direction due to high-pressure cleaning. So always wear waterproof and protective gearing.

  • Risk of electric shock in an electric power washer.

How Does A Pressure Washer Work FAQ’S

How does a pressure washer pump work?

The pump of a pressure washer is a normal water pump that works with an electric motor. The pump accelerates the water that washer intake from the faucet and then runs in the hose to reach the trigger gun.

How does a pressure washer unloader valve work?

When a spray gun is not in use, then unloader valve works to resist the flow of water to the pump. It is also used to regulate the pressure output from the pump.

How does a pressure washer trigger work?

The trigger gun pushes out the water from the trigger when the unloader allows the water. The water is sent to the gun and the one who is operating the pressure washer would depress the trigger to allow the spraying water.

How do you turn on a pressure washer?

It is really easy to turn on a pressure washer. Connect one end of the hose to pressure washer and other to the water outlet. Select and secure your nozzle. Release the water from faucet Turn ON the motor switch to start it.

Is 2000 psi enough for a pressure washer?

Most of the gas-powered pressure washers use 2000-2800 PSI to effectively clean the floors, concrete surfaces, and patios. The pressure washers with 2000 PSI are mostly used by professionals and experts.


If you want to have a pristine clean patio, backyard furniture or vehicle pressure washer is the best product. A pressure washer is really a very efficient and useful tool. It saves a lot of time, labor and water.

Now that you have understood the working and structure it would be easier for you to decide on which model would work best for your needs. So analyze your budget, your washing needs and make the buying decision wisely.