PSI question use with different tools

[vincent]

Fellow cleaner and I discussing the psi on different tools we use.

We basically have the same machines, both TNT's.

He runs his greenhorn at 500psi, I run mine 550psi.

He runs his 360i at 250, mine at 425. Why, because while testing mine, I see a 200 psi drop from what its set atm. Now I understand this, using high flow, but with the 3 standard jets on the 360i, I don't see the reason for the drop.

Any thoughts.

 

[dgardner]

The standard 360i jetting is '03, right? (3 X '01)

Are you saying that the pressure measured out at the 360i is 200 psi less than the atm gauge with water flowing? With a 100' hose, you would expect only around 50-70 psi drop, so the remaining drop is probably due to fittings. I have seen so-called 1/4" fittings (cheap) that have actual passages much less than 1/4", and also fittings that have very small passages due to mineral build-up. Descaling will help the latter, but the former requires changeout of the fittings.

If you're running a lot more than 100' of hose, or if your hose run is comprised of a bunch of shorter lengths coupled together (many more fittings), then your pressure drop will be greater.

If you're saying the atm pressure reading drops 200 psi when you key the 360i, that's a whole different problem - pump, pressure reg, etc.