How to Use a Pressure Washer

Discover various ways of using a pressure washer for decks, fences, and more.

A pressure washer on a desk

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Whether you are dealing with a dirty fence, stained concrete, or aged deck, a pressure washer is an effective tool to clean dirt, dust, and other debris from the surface. Instead of trying to clean the surface with a standard garden hose, you can connect the hose to the pressure washer in order to increase the power of the spray. This allows the pressure washer to remove dirt and grime that is deposited deep in porous material, which is why pressure washers are so effective at cleaning wood, brick, mortar, and paving tiles.

However, you can't simply grab a pressure washer and start spraying without risking damage to the surface you are trying to clean. Keep reading to learn about the various parts of a pressure washer, the dangers of using a pressure washer, and how to use a pressure washer properly.

What Is a Pressure Washer?

Most people have heard of a pressure washer, but may not have a firm understanding of exactly what this tool is and how it's used. A pressure washer is an electric or gas-powered tool that is designed to intake water from a garden hose and spray it out at a greatly increased water pressure. This is achieved with a mechanical pump that forces the incoming water up through a narrow hose and out through a nozzle to help direct the flow of the water.

Parts of a Pressure Washer

There are five main parts of a pressure washer that are important to know and be able to identify before you start working with one of these tools.

  • Motor/Engine: The motor or engine can run on either gas or electricity. If you have an electric pressure washer, then you will need to plug it into an available electrical outlet in order to run this machine, but if you have a gas-powered pressure washer, then you will have to ensure the tank is filled before trying to use the pressure washer.
  • Water Pump: The water pump is the part of the pressure washer responsible for pumping the water with enough force to generate the high-pressure output used for cleaning tough, porous material.
  • Water Inlet: Connect the garden hose to the water inlet to provide a constant supply of water to the pressure washer.
  • High-Pressure Hose: After the water flows into the pressure washer, it's pumped out through the high-pressure hose. These hoses can range in length, though they are typically about 20 to 50 feet.
  • Wand and Nozzle Attachments: At the end of the high-pressure hose is the wand and the currently installed nozzle attachment. The wand is used to control the direction and output of the pressure washer. You need to squeeze the trigger on the wand for the water to spray out of the nozzle at the end of the wand. There are a variety of nozzle attachments to choose from based on the angle of the spray pattern, from white nozzles at 40 degrees to red nozzles at 0 degrees.

Safety Considerations

Spraying yourself in the face with a garden hose will probably be a bit surprising and possibly unpleasant, but depending on how hot it is outside, it could just be refreshing. Spraying yourself in the face with a pressure washer can result in permanent damage to your eyes, as well as severe bruising and abrasions on the skin, so it's better to learn how to handle this tool properly.

Always wear protective eyewear, closed-toe shoes, and gloves to help keep you safe while you work. Also, pay attention to where you are directing the pressure washer. Avoid electrical outlets, lights, windows, and loose gravel that can be kicked up by the force of the spray. It's recommended to cover foliage before using a pressure washer so that sensitive plants are protected from the powerful spray.

Additionally, it should be mentioned that using a pressure washer on a ladder is a bad idea. If you know anything about physics, then you know that for every action, there is an equal and opposite reaction. Put plainly, the force generated by the pressure washer will force the water out forwards at a very high pressure, but it also pushes back against the user, which can cause them to fall backwards off a ladder.

Gas powered pressure washers are stronger than electric models and should be used with discretion in order to avoid damage to the pressure washed material.

How to Use a Pressure Washer

  1. Choose a Nozzle for the Pressure Washer

    You will need to choose a nozzle attachment in order to help control the spray from the pressure washer. It's recommended to start with the nozzle attachment that has the widest spray fan pattern and lowest water pressure output, which should be the white nozzle.

    • White nozzles have a 40-degree fan pattern spray that is better for softer surfaces.
    • Green nozzles have a 25-degree fan pattern spray that is slightly more powerful than the white nozzle.
    • Yellow nozzles have a 15-degree fan pattern spray, which is significantly more powerful than the white nozzle.
    • Red nozzles have a direct, 0-degree spray pattern that provides the most powerful output. Take care not to damage the target surface if you opt for a red nozzle.
    • Black nozzles are made for dispensing soap. They restrict the flow of the liquid to better apply the soap to the surface.
  2. Connect and Turn On the Pressure Washer

    Plug in the pressure washer or fill the gas tank, depending on whether you have an electric or gas-powered machine. Connect the garden hose to the pressure washer inlet, then turn on the garden hose. A cleaning agent can be added to the reservoir on a standard pressure washer or poured into a bucket for use with a siphon system.

    Connect the high-pressure hose to the pressure washer, then turn on the pressure washer and set it to the lowest power setting. Make sure that the nozzle is pointed away from you in the direction of the target surface.

    Grip the wand and pull the trigger to start spraying. Starting on low power helps to avoid accidentally damaging the target surface with a powerful burst of water at close range, but you should still start in a small corner or inconspicuous section in case there is some marking or damage from the water.

    Tip

    To help prevent damage to the target material, it's recommended to hold the nozzle about four to eight feet away from the target surface and at an angle of about 20 to 45 degrees. Keep in mind that you can always move closer to the target surface if necessary, but if you start too close, the damage will already be done.

  3. Adjust the Aim of the Nozzle

    Pressure washers are powerful tools that need to be handled carefully. With the widest-angle nozzle attached, standing about eight feet from the target surface, aim the nozzle at a 40-degree angle and begin spraying the target surface.

    As soon as the water starts spraying from the pressure washer, you should be able to see whether the high-pressure spray is effective at the current distance. At this distance and angle, the water shouldn't damage the surface of wood, brick, concrete, or cement, but it could still break glass and electrical fixtures, so make sure you avoid these delicate objects.

    If the spray isn't cleaning the surface very well, move towards the target surface and adjust the angle of the nozzle to increase the force at which the spray is hitting the surface. You can also swap the white nozzle out for a nozzle with a more direct spray.

  4. Work in Horizontal Lines From the Top Down

    Once you find the nozzle, spray angle, and distance that works to clean the surface without damaging the material, you can start to work from the top edge down to the bottom of the material. If you are cleaning a fence, start at the top and spray long, horizontal swathes across the fence, gradually moving down the fence until you reach the bottom.

    This method takes advantage of gravity to help drain away the water and avoid creating dirt lines in the material. You can follow a similar pattern for surfaces that are underfoot, like a driveway or deck. Choose one size that will serve as the top and gradually work your way down to the bottom by cleaning in long horizontal lines.

  5. Clean the Pressure Washer Water Lines

    If you used soap or detergent to help clean tough stains and stuck-on grime, then you will need to clean the water lines in the pressure washer to avoid soap scum clogs. It's recommended to clean the water lines as soon as you are done working so that the soap doesn't have the opportunity to dry inside the pressure washer.

    Refill the pressure washer with washer and run it for about 3 to 5 minutes in order to thoroughly rinse the water lines. When you are confident that the soap has been rinsed out of the pressure washer, empty the tank and wipe it down with a microfiber cloth before storing the pressure washer in the shed or garage.