surface scrubber

[vhayes]

You are spot on with nozzles. You read the chart right, but if you would like to work out the math, the formula looks like this:



Your GPM is, of course, cut in half with the two nozzles on a 16" surface cleaner, so it is 2.8 x the square root of 1.6. This is a 3.5 nozzle.

Adding hose can cause pressure loss, but it is negligible. Here is a chart explaining pressure loss, but it will be less than 10 PSI for your additional hose. http://www.ultimatewasher.com/hose-pressure-loss.htm

I would try to diagnose it the way computer people diagnose problems. Replicate the situation. If no pressure loss is noted, it had something to do with that customer's water supply, as Doug and Larry mentioned above (Great info, Larry). If you have the same problem, try replacing the hose in question with a different one. If that fixes it, then it is the hoses fault. If your surface cleaner has a hard time with over 100 ft of hose no matter what hoses you use (as Doug mentioned), then you know your limitations here, and I would run a longer supply like he mentioned. Eliminate things this way and you will find the component with the problem.

 

[Sirocco Jerry]

Line-Loss in pressure hose vs. Big flow with wimpy pressure

Adding hose can cause pressure loss, but it is negligible. Here is a chart explaining pressure loss,
but it will be less than 10 PSI for your additional hose. http://www.ultimatewasher.com/hose-pressure-loss.htm

Good input, but allow me to add..

When you look at a pressure loss chart remember..
that's before you add "ends" on that hose..
3/8" i.d. hose has ends that are barely 1/4"i.d.
add this to the line-loss and the actual loss is more than negligible.
For all you guys with 5gpm and more..
You know you will stretch out a couple hundred freet of hose from time to time..
If you only have 2500psi.. you are spending money on Horsepower that is not delivering performance..
5.5gpm and 2500 psi.. thru 200ft hose.. you have less actual workspeed than with 4gpm at 4000 psi
..assuming you're "pressure" washing.

On the same note..
Big companies sell 8 and 10gpm machines at 2500 to 3000 psi.
I push 7gpm 4000 psi machines because nobody wants to pull a 1/2" hose,
and.. more pressure "delivers" cleaning power easier,
.. with less fuel cost.

And.. avoid lots of "ends" (aka..flow-resdtrictors) in the hose, between the machine and your wand.

..and if you have an 8+gpm machine..
consider 150ft of 1/2" hose on your reel, and a 25ft section of 3/8" at the "business end".. to get 200 ft.