[A Foster]

Hi All.

i am considering upgrading my 6.5hp pressure washer to a more powerful unit but not sure what is most practical.

Most of my work for the machine will be targeted at cleaning drives, patios, small car parks etc, but I want a machine that I won't have to upgrade again soon.

I started with a 6.5hp chinese PW and cheap rotary cleaner which both did the job well but i'm assuming that a more powerful and better quality set up will get the jobs done quicker and better.

The whole Psi and Litres p/m is confusing me a bit.

I've heard that the Litres per minute is more important, so does that mean if 2 pressure washers were available, 1st with 3000psi 12 L/p/m and the 2nd 2500psi 15 L/p/m the 2nd would be a better more appropriate tool?

Is it the amount of water flow that cleans or the actual pressure, or a good combination of both?

Any information on what sort of machine / pressure / LPM etc would be appreciated. Also, can you run more powerful machines from a normal household external tap or would I need a water tank?

I don't want to sound rude, but I would appreciate actual advice rather than links to pressure washer sales websites. Links to information would be good.

Thanks

[george garwol]

I'm after going into powerwashing recently, and there is few things i can see about psi and flow.
my rig is 3000psi 20lpm and im happy with it. Few lads around use 3000psi 15lpm honda driven Pwashers (Comet or Interpump).
you can do jobs with 2200psi and 12lpm, but job is very slow then.
I could see that 3000psi cleans concrete well.
gear over 3000psi goes expensive.
Average flow out of outside taps around my town is 10-14 lpm, so i had to get buffer tank which is 600l and is big enough. comparing between Pwasher 2200psi  12lpm what i had before, to 3000psi 20lpm what i use now is nearly half time at the job, and job is done way better.
I have no experience with pressures higher than 3000psi so can say nothing about it.

[BDCS]

Imagine the flow and pressure thing like this :-
Ride a push bike into a wall at 30mph - damage the wall ?
Drive a lorry into a wall at 25mph - this will damage the wall !
 The pressure relates to the speed and the flow to the weight - slightly less pressure is more than made up by the increase in flow.

[A Foster]

Thanks for replies. That makes sense.

What is difference between comet and interpump?

[BDCS]

I run Interpump but both have supporters - any pump will be fine so long as you can get spares, valves and have an external unloader that runs back to tank - swerve the unloaders that recirculate into the pump intake as they overheat.