[evil genius]

hi all.
im fairly new to pressure washing and we have just bought one to wash down our plant and customers property's when finished.

whats the safest way to reduce pressure on our machine? we have a 13hp, 3500psi/15lpm.
i presume by just lowering the revs we are reducing pressure but also flow. how do i keep optimum flow but reduce the pressure?

thanks.
ian

[BDCS]

Increase the nozzle size !

http://server23.sitewizard.co.uk/sites/malcleansenew/images/Info%20Sheets/Nozzle_Chart.pdf

[Cliff Horne]

So will decreasing the nozzle size give my FSC more "cutting power" or will it just damn up PW.

I only ask as I've been asked to clean and create a "roughed up" surface on a porous tarmac tennis court so it will act as a key for screeding on a new surface, dont want to damage FSC or PW.

Cliff

[BDCS]

No, for given revs the pump will give a set flow. If you alter the nozzle it will change the resistance to the flow which is the "Pressure". Fitting a smaller nozzle will give full pressure but at a lower flow and cause the rest of the flow to unload. I'd fit one arm with a zero degree nozzle to key the surface - but the normal size.

[Cliff Horne]

Cheers I'll give it a go if I get the job

[evil genius]

thanks for the reply and posting that chart up.

according to the chart my machine needs a 04 size nozzle to opperate at it 250bar/15lpm,
so if i want 150bar/15lpm i need nozzle size 055?

thanks,
ian

[BDCS]

Yes

[evil genius]

Perfect, thanks for your help