New Pressure Washer for My Window Cleaning Business

[windowrescue]

Good afternoon everyone,

I just purchased a 4 GPM 4,000 psi machine for my business. I've done quite a bit of reading on the forum, but am hopeful to have some help in a few topics which I've been unable to figure out.

I'm looking to add the following two services to my business: softwashing of homes and driveway/flat surface cleanings. The two questions I have so far are with regards to the nozzle tips. I've pulled up the nozzle tip chart on PressureTek and cant make sense of it. I've seen a few others on different websites and have the same issue. I feel like I'm 1/2 retarded. Is there a tip, or range of tips which I should be looking for for my wand?

Along the same lines, I've seen some posts where surface cleaners apply too much pressure to new-ish concrete; I've seen other members state that 4,000 psi is too harsh and can ruin the cream. How could I figure out an appropriate tip for surface cleaning driveways?

Again, I appreciate all help.

Thanks,

Richard
Window Rescue Window Cleaning
DFW

[Bob Williamson]

On the left of the nozzle chart is the gpm and the top is your desired psi. Intersect the two and that is the orifice size you need to create that pressure. To lower the pressure on your surfacer, select the desired psi, insect it with your gpm then divide that orifice size by 2 because your surfacer has two nozzles not one.