Pressure washers are no joke! It's just water, so it may not seem that dangerous, but they said the same thing about Niagara Falls. The average garden hose with a spray attachment will send water out at 40psi. A typical pressure washer sends the water out at 1500psi, so that's more than thirty-seven times the pressure. This is what makes pressure washers so amazing, the water that comes out of these things is like a razor blade that cuts through dirt and grime without damaging the surface.
In other words, don't use it to wash your hands.
Gas or Electric?
If you're choosing whether to buy a gas pressure washer or an electric pressure washer, use an electric. A gas powered washer is for really heavy duty jobs. We're talking about hosing down Mack trucks and roads and industrial buildings. You're liable to break a window using one of those on your car. Stick to electric. Electric brings more than enough power for the job.
In particular, look for an electric washer with 1200-1900 psi. Any more than that and you're going to be scraping paint chips off your car when you're done washing it.
Select the Right Nozzle
Nozzles are color-coded for ease of use. Yellow are for sidewalks and stripping paint. Red is for deep-scrubbing on cement surfaces.
You're looking for a green nozzle to blast the debris off of your car for the pre-wash rinse, and white to spray the detergent off when you're done cleaning.
The Cleaning Process
The basic process is simple.
- Give the car a good hose-down with the green nozzle.
- Add a quart of detergent to a bucket of water, stir, and use it to fill the detergent tank of your pressure washer.
- Select "detergent" on your washer and spray your car down, from the top to the bottom.
- Let detergent sit for five minutes.
- Rinse with the white nozzle, working top to bottom at a downward angle.
And there you go! You can dry the car however you please, with a towel, a chamois, or a quick drive around the neighborhood.