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Pressure washers are a fast, convenient way to remove gunk, but they can also be VERY dangerous if used improperly. They work by taking in low-pressure water, turn it into a super high-powered stream (with a gas or electric motor), then through a nozzle where it can be so strong, it can actually damage wood/stone and inflict serious harm to people and animals.

Pressure is measured in PSI (pounds per square inch) — the higher it is, the stronger and (usually) more efficient the washer is. That stream of water is then forced through a nozzle at a varying degree of spray pattern. The lower the number, the more concentrated (and damaging) the pressure becomes.

Be very careful about how you use a pressure washer as damage can void the warranty of whatever you were washing

What Pressure Washers Can Be Used For

Craftsman CMXGWAS021022 (Gas) /Craftsman

Great Uses

Some ways a pressure washer is excellent for:

  • Stripping old paint from patio and fences
    • Don’t hold the nozzle too close!
    • Wash length-wise
  • Concrete driveways
  • Outdoor tools and gear
  • Outdoor cushions
  • Garbage cans

Use With Caution

What some people say pressure washers are good for, though many experts advise against it. If you MUST do it, you will have to be extremely careful:

  • Removing algae off roof shingles (although those blue-green algae do not damage the roofing)
    • It’s best to use a moss/mold killer spray instead (a pressure washer can loosen up shingles)
  • Bikes
    • Be extra careful around the seat and tires
  • Washing cars
    • Pressure can damage paint and can lead to rust. Use VERY low pressure!
    • Be extremely careful when washing the windows and any other glass

NEVER aim a pressure washer nozzle at an animal or human being. Serious harm or death can result!


Sun Joe SPX3000 (Electric) /Sun Joe

Before Use

  • Learn how to quickly turn off the pressure washer in case of an emergency
  • Practically every pressure washer is so loud, ear plugs should be used to prevent hearing damage
  • Start with low pressure first so you don’t accidentally dent or wash something unexpected away
    • Start in a hidden spot as a test
  • Nozzles usually range from 0 – 40 degrees (how wide the spray stream goes)
    • Start with 40 degrees first and at a greater distance from what is being washed
  • Never set a pressure washer nozzle to 0 degrees
    • Pressure at 0 is so strong, it can cut through metal!
  • Pressure washer can dislodge particles and shoot them with great force
    • Wear protective boots
    • Wear protective glasses
    • Wear protective gloves
  • NEVER EVER point the pressure washer at any living being!
  • Add soap/cleaning solution according to instructions
  • Purge any leftover air from the pump before use
    • Turn on water and squeeze the trigger at the lowest pressure until the stream comes out in an uninterrupted manner
  • Use the pressure washer on as even and stable a surface
    • Ladders: the washer can produce so much kickback, it could throw you off balance
  • Obviously, don’t spray at any electrical power source unless you want to be electrocuted!

After Use

  • Never leave the pressure washer unattended while it is still on!
  • Do NOT point the nozzle at anything (or ANYBODY) to prevent accidental discharge
  • Purge any leftover pressure before removing the hose
    • Turn off pressure washer, engine, and then the water
    • Gently squeeze the trigger until pressure is relieved
  • Drain any leftover water from the hose
  • Thoroughly clean and empty the water and detergent tanks

Simpson MSH3125 (Gas) /Simpson Cleaning

Which Pressure Washers Are Good?

  • Sun Joe SPX3000 Electric Washer ($150)
    • One of the most affordable washers available, though it only outputs up to 2,030 psi
    • Suitable for most consumers
  • Simpson Cleaning MSH3125 Gas Washer ($400)
    • Heavy-duty washer (at 3,200 psi) with large tires that can be brought around construction sites
  • Craftsman CMXGWAS021022 Gas Washer ($370)
    • Heavy-duty washer (at 3,000 psi) made in the USA