Why do I have an orifice on my spot free solenoids

[wash4me]

3/32" is the size of orifice on my solenoids on the ro stand that go out to the spot free function. Why do I need an orifice on these? I am wanting more spot free pressure and flow than I have.

 

[MEP001]

The orifice is what the plunger seats on to stop flow. If the orifice was bigger, it would decrease the MOPD, in other words you'd have to run the pump at an even lower pressure. Typically a 3/32" can run 250 PSI, 1/8" at 150, 5/32" at 100. If you want to increase both flow and pressure, you need a pilot-operated solenoid like this:

https://www.dultmeier.com/products/search/6027

That's what I use on spot-free running 450 PSI to the bays.