I’m sure someone can jump on here and break down all of the physics… not me lol
I first tried a 5gpm 60 psi… could hardly get the water out of the line. I spoke to a couple of guys and one broke it down why it wouldn’t work and why I needed less volume and more pressure. That was probably 5 years ago so I can’t remember the entire explanation
But once I went to the 2 gpm and the higher 100psi I never looked back. Sure we have gone through a few pumps over the years but when you can run two poles 4-5 stories it’s all worth it. (Currently also using a flow controller we built and that helps us to control our pressure +/- as well as preserve the life of the pumps)
I agree with your point on the pressure washer… however many things come into play here to increase volume properly. I.E.: surface cleaner? Does it have a dual bar with four jets or a single with two? What’s the orface size? Is it allowing full flow or restricting flow?
My point is yes adding more GPM seems like the best idea but only if it is calculated correctly. However I can’t compare WFP to pressure washing because it’s not “water pressure” that cleans the surface but the agitation from the brush as you already know.
If you were closer I’d let you check out our van set up so you could see what can be accomplished with the set up described
Laminar flow low pressure pencils, backpack, and a cationic silicone additive for eliminating water tension to sheet the water for a perfect drain down. Even high TDS will leave a spot free surface. Not to use an nonionic surf because it leaves a film. I have done it. It does work. But requires a bit of technique. No suds. And cannot be done in the sun.
This has been a awesome thread. So to answer a few questions. There is water flow rate and water restriction. To increase water flow rate you can increase the ID of hose. To increase flow restriction you step down the ID of the hose or jet. So to get more water flow use 1/2 hose with a 3/8 ID from your filter to the pole hose. The pole hose used by all WFP is OD 5/16 inside diameter 3/16. This reduction will increase the water pressure not flow rate. The next reduction is the jets. Most pencil jets are 1/8 opening. Fan jets are even smaller. Tucker brush using the ASH model has 2 sizes of screws. One is a larger than 1/8 opening.
So try this configuration and see if you get the desired result you want.
Personally I use a tank based system with a flow controller. I get more than enough water flow at the brush to clean windows using a 24 inch Unger Nlite brush with 4 jets. 90% of my work is commercial mid rise.
