Water Preasure Or Volume, Does It Matter?

[lovenhim]

Hello everyone. I have not been on the forum for a while. I have some questions. Which is more impirtant, water preasure or volume? I have and use a large diametor commercial water hose. I think it is one inch but not sure. I have and use the AutoGeek foam gun with its quick connect nossle. I also have a firemans nossle from AutoGeek. When wetting or rinsing our car I prefer the fireman nossle. It flows more volume meaning water flows in sheets off the car. Sure some use a preasure washer and foam cannon but I do not own any of that. Which do you prefer, preasure or volume? Why?

[North1Star]

Both pressure and water. High pressure will help the foam/water penetrate the dirt film, while more water will help rinsing the dirt more quickly

As a matter of fact, pressure washers with lower than average GPM dont clean as good as pressure washers with high GPM ... as I have read

[mdbenge]

Both are important, not sure if they are equally important but don't have any way to move the scales.

Pressure washer ratings are based on an equation of Pressure (PSI) x Gallons Per Minute (GPM) == 'Cleaning Units' [PSI / GPM does not reduce easily so they refer to it as "Cleaning Units" or effectiveness]

[SWETM]

To give an example if you would chose between a PW with 2000psi and 1.4gpm or a PW with 1400psi and 2.0gpm. I would go with the 1400psi and 2.0gpm PW. And if between those specs if you have another choice I would go with the highest gpm. What many can be confused with is that it's most often the specs of the PW pump and not what you get from the nozzle tip. They do try to suit the orifice in the nozzle tip and what the spray gun so it delivering the specs. But that it's not the case what the real working specs are. There will not be a large difference between them. But a little better cleaning ability and faster rinsing with the 1400psi and 2.0gpm PW.

Then I think it's also how you are going to be useing the PW. Are you going to use as you use your hose and basicly rinse with it. Or are you going to use it to use the water pressure from the PW to clean with. Many says that you don't need more than 1000psi and it's a safe to use on the vehicals. I think it's too low to be cleaning with. And you are moving the nozzle dangerously close to the paint to get effective. To get effective and able to clean wider with the water pressure from the PW. I like to use a 15 angle nozzle tip or 25 angle nozzle tip and at least 1600psi-1700psi from the nozzle tip and move the nozzle a little longer away from the vehicals. This I know is a trouble for you with 110v electric outlets as standard. We have 240v electric outlets as standard here in Sweden. And we can then have a stronger electric motor on those voltage. Cause if you have 1700psi and to get the water flowing you need around 1.6-1.8gpm. Or you will have a steam of water or how you would explain it if holding it longer away. But then with a 15 angle nozzle tip it could work with a lower gpm. The smaller specs PW do clean but the width is not so effective to clean with as it's so narrow that it takes a long time to clean the car with. With a wider nozzle tip you get a less effective cleaning ability from it as you get a wider spread of the water. So it's a lot depending on how you will use it. And if you have a very good pressure from your 1" garden hose with a high gpm from it. You can be very disappointed with a smaller specs PW. Cause the garden hose would be cleaning it just as well but a lot quicker. If you have the possibility to loan and test a PW with the specs you are consider to buying would be great. So you can see if it's worth it to you to buying one. I could not live without my PW LOL. It's a Kärcher K7 electric pressure wash with specs 2600psi 2.6gpm. And the working pressure psi is 2200-2300psi on the highest setting. I can switch the pressure on the spray gun handle from that down to 1000psi. And when cleaning the cars I always use the highest setting. Holding it 1 1/2 feet away of the car I get an awesome coverage when cleaning and it's goes fast to clean after foamed the prewash foam with the foamcannon. And don't be worried about the foamcannon don't get an acceptable foam from it. The switch from the original orifice 1.25mm to the smaller 1.1mm orifice in the foamcannon. Makes the smaller PW work good with a foamcannon. Concentrate on what specs you would want in your needs from a PW. And remember that you can use it to clean a lot of stuff around the house and on the house LOL. I cleaned the roof on the house I live in this summer. And the walking path tiles in the garden looks like new.

/ Tony

[FUNX650]

IMO:
Both are good to have on hand; but be
prudent when directing pressurized water
at vehicles—especially their paint.
(Think in terms of:
moderation/undulation/oscillation.)

•Just as in buffing paint, focusing too much
pressure, (in this case: water pressure), on
one area of the paint for too long may cause
damages to occur.



Bob

[DBAILEY]

Pressure when trying to blast off the loose dirt prior to washing, then high volume to flood the panel for rinsing away the wash soap.